diff --git a/src/libanalyzer/java/com/android/tools/r8/libanalyzer/LibraryAnalyzerCommandParser.java b/src/libanalyzer/java/com/android/tools/r8/libanalyzer/LibraryAnalyzerCommandParser.java
index 1f5b210..2e73b3b 100644
--- a/src/libanalyzer/java/com/android/tools/r8/libanalyzer/LibraryAnalyzerCommandParser.java
+++ b/src/libanalyzer/java/com/android/tools/r8/libanalyzer/LibraryAnalyzerCommandParser.java
@@ -15,12 +15,12 @@
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.origin.PathBasedMavenOrigin;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.FlagFile;
 import com.android.tools.r8.utils.Reporter;
 import com.android.tools.r8.utils.StringDiagnostic;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.internal.ArrayUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableSet;
 import java.io.File;
 import java.io.IOException;
diff --git a/src/main/java/com/android/tools/r8/ArchiveClassFileProvider.java b/src/main/java/com/android/tools/r8/ArchiveClassFileProvider.java
index c28ab68..02d95df 100644
--- a/src/main/java/com/android/tools/r8/ArchiveClassFileProvider.java
+++ b/src/main/java/com/android/tools/r8/ArchiveClassFileProvider.java
@@ -3,8 +3,8 @@
 // BSD-style license that can be found in the LICENSE file.
 package com.android.tools.r8;
 
-import static com.android.tools.r8.utils.FileUtils.CLASS_EXTENSION;
-import static com.android.tools.r8.utils.FileUtils.isArchive;
+import static com.android.tools.r8.utils.internal.FileUtils.CLASS_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.isArchive;
 
 import com.android.tools.r8.ProgramResource.Kind;
 import com.android.tools.r8.errors.CompilationError;
@@ -13,9 +13,9 @@
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.origin.PathOrigin;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.OneShotByteResource;
 import com.android.tools.r8.utils.ZipUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.io.ByteStreams;
 import java.io.Closeable;
 import java.io.IOException;
diff --git a/src/main/java/com/android/tools/r8/ArchiveProgramResourceProvider.java b/src/main/java/com/android/tools/r8/ArchiveProgramResourceProvider.java
index 80c6a1d..0823bf5 100644
--- a/src/main/java/com/android/tools/r8/ArchiveProgramResourceProvider.java
+++ b/src/main/java/com/android/tools/r8/ArchiveProgramResourceProvider.java
@@ -10,9 +10,9 @@
 import com.android.tools.r8.origin.PathOrigin;
 import com.android.tools.r8.utils.ArchiveResourceProviderUtils;
 import com.android.tools.r8.utils.ArchiveResourceProviderUtils.ProgramResourceFactory;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.OneShotByteResource;
 import com.android.tools.r8.utils.ZipUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import java.io.IOException;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Path;
diff --git a/src/main/java/com/android/tools/r8/ArchiveProtoAndroidResourceProvider.java b/src/main/java/com/android/tools/r8/ArchiveProtoAndroidResourceProvider.java
index ca4321e..25e8839 100644
--- a/src/main/java/com/android/tools/r8/ArchiveProtoAndroidResourceProvider.java
+++ b/src/main/java/com/android/tools/r8/ArchiveProtoAndroidResourceProvider.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.origin.ArchiveEntryOrigin;
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.origin.PathOrigin;
-import com.android.tools.r8.utils.FileUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.io.ByteStreams;
 import java.io.ByteArrayInputStream;
 import java.io.IOException;
diff --git a/src/main/java/com/android/tools/r8/BackportedMethodList.java b/src/main/java/com/android/tools/r8/BackportedMethodList.java
index 1398cd5..b757d2c 100644
--- a/src/main/java/com/android/tools/r8/BackportedMethodList.java
+++ b/src/main/java/com/android/tools/r8/BackportedMethodList.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.keepanno.annotations.KeepForApi;
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.utils.ExceptionUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 
 /**
  * Tool to extract the list of methods which is backported by the D8 and R8 compilers.
diff --git a/src/main/java/com/android/tools/r8/BaseCompilerCommand.java b/src/main/java/com/android/tools/r8/BaseCompilerCommand.java
index 4c27ffb..d2cf7b5 100644
--- a/src/main/java/com/android/tools/r8/BaseCompilerCommand.java
+++ b/src/main/java/com/android/tools/r8/BaseCompilerCommand.java
@@ -21,14 +21,15 @@
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.AndroidApp;
 import com.android.tools.r8.utils.DumpInputFlags;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.InternalOptions.DesugarState;
 import com.android.tools.r8.utils.ListUtils;
 import com.android.tools.r8.utils.MapConsumerUtils;
 import com.android.tools.r8.utils.PartitionMapZipContainer;
 import com.android.tools.r8.utils.ProgramConsumerUtils;
 import com.android.tools.r8.utils.Reporter;
+import com.android.tools.r8.utils.StringDiagnostic;
 import com.android.tools.r8.utils.ThreadUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import java.nio.file.Path;
 import java.util.ArrayList;
 import java.util.Arrays;
@@ -817,7 +818,8 @@
       if (mode == null) {
         reporter.error("Expected valid compilation mode, was null");
       }
-      FileUtils.validateOutputFile(outputPath, reporter);
+      FileUtils.validateOutputFile(
+          outputPath, errorMessage -> reporter.error(new StringDiagnostic(errorMessage)));
       if (getProgramConsumer() == null) {
         // This is never the case for a command-line parse, so we report using API references.
         reporter.error("A ProgramConsumer or Output is required for compilation");
diff --git a/src/main/java/com/android/tools/r8/BaseCompilerCommandUtils.java b/src/main/java/com/android/tools/r8/BaseCompilerCommandUtils.java
index 03d5b0c..a4169b5 100644
--- a/src/main/java/com/android/tools/r8/BaseCompilerCommandUtils.java
+++ b/src/main/java/com/android/tools/r8/BaseCompilerCommandUtils.java
@@ -3,7 +3,7 @@
 // BSD-style license that can be found in the LICENSE file.
 package com.android.tools.r8;
 
-import com.android.tools.r8.utils.FileUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import java.nio.file.Path;
 
diff --git a/src/main/java/com/android/tools/r8/ClassFileConsumerUtils.java b/src/main/java/com/android/tools/r8/ClassFileConsumerUtils.java
index 6c83349..02abecd 100644
--- a/src/main/java/com/android/tools/r8/ClassFileConsumerUtils.java
+++ b/src/main/java/com/android/tools/r8/ClassFileConsumerUtils.java
@@ -4,8 +4,8 @@
 package com.android.tools.r8;
 
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.ZipUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.io.ByteStreams;
 import com.google.common.io.Closer;
 import java.io.BufferedOutputStream;
diff --git a/src/main/java/com/android/tools/r8/D8.java b/src/main/java/com/android/tools/r8/D8.java
index 59fe153..4806dea 100644
--- a/src/main/java/com/android/tools/r8/D8.java
+++ b/src/main/java/com/android/tools/r8/D8.java
@@ -48,8 +48,8 @@
 import com.android.tools.r8.utils.ExceptionUtils;
 import com.android.tools.r8.utils.InternalOptions;
 import com.android.tools.r8.utils.StringDiagnostic;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.ThreadUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.timing.Timing;
 import java.io.IOException;
 import java.util.ArrayList;
diff --git a/src/main/java/com/android/tools/r8/D8Command.java b/src/main/java/com/android/tools/r8/D8Command.java
index a264fc2..9210491 100644
--- a/src/main/java/com/android/tools/r8/D8Command.java
+++ b/src/main/java/com/android/tools/r8/D8Command.java
@@ -34,7 +34,6 @@
 import com.android.tools.r8.utils.AndroidApp;
 import com.android.tools.r8.utils.AssertionConfigurationWithDefault;
 import com.android.tools.r8.utils.DumpInputFlags;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.InternalGlobalSyntheticsProgramProvider;
 import com.android.tools.r8.utils.InternalOptions;
 import com.android.tools.r8.utils.InternalOptions.DesugarState;
@@ -46,6 +45,7 @@
 import com.android.tools.r8.utils.StringDiagnostic;
 import com.android.tools.r8.utils.ThreadUtils;
 import com.android.tools.r8.utils.ZipUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.io.ByteStreams;
 import java.io.IOException;
diff --git a/src/main/java/com/android/tools/r8/D8CommandParser.java b/src/main/java/com/android/tools/r8/D8CommandParser.java
index 056daf6..2453fbb 100644
--- a/src/main/java/com/android/tools/r8/D8CommandParser.java
+++ b/src/main/java/com/android/tools/r8/D8CommandParser.java
@@ -9,10 +9,10 @@
 import com.android.tools.r8.profile.art.ArtProfileProviderUtils;
 import com.android.tools.r8.profile.startup.StartupProfileProviderUtils;
 import com.android.tools.r8.utils.ExceptionDiagnostic;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.FlagFile;
 import com.android.tools.r8.utils.StringDiagnostic;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Sets;
diff --git a/src/main/java/com/android/tools/r8/DataEntryResource.java b/src/main/java/com/android/tools/r8/DataEntryResource.java
index 899c5a6..fa09b25 100644
--- a/src/main/java/com/android/tools/r8/DataEntryResource.java
+++ b/src/main/java/com/android/tools/r8/DataEntryResource.java
@@ -3,7 +3,7 @@
 // BSD-style license that can be found in the LICENSE file.
 package com.android.tools.r8;
 
-import static com.android.tools.r8.utils.StringUtils.UNIX_LINE_SEPARATOR;
+import static com.android.tools.r8.utils.internal.StringUtils.UNIX_LINE_SEPARATOR;
 
 import com.android.tools.r8.keepanno.annotations.KeepForApi;
 import com.android.tools.r8.origin.ArchiveEntryOrigin;
diff --git a/src/main/java/com/android/tools/r8/DexFilePerClassFileConsumer.java b/src/main/java/com/android/tools/r8/DexFilePerClassFileConsumer.java
index cdd2e1d..ec385c5 100644
--- a/src/main/java/com/android/tools/r8/DexFilePerClassFileConsumer.java
+++ b/src/main/java/com/android/tools/r8/DexFilePerClassFileConsumer.java
@@ -3,7 +3,7 @@
 // BSD-style license that can be found in the LICENSE file.
 package com.android.tools.r8;
 
-import static com.android.tools.r8.utils.FileUtils.DEX_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.DEX_EXTENSION;
 
 import com.android.tools.r8.keepanno.annotations.KeepForApi;
 import com.android.tools.r8.utils.ArchiveBuilder;
diff --git a/src/main/java/com/android/tools/r8/DexRoundTrip.java b/src/main/java/com/android/tools/r8/DexRoundTrip.java
index fcf308b..f83828a 100644
--- a/src/main/java/com/android/tools/r8/DexRoundTrip.java
+++ b/src/main/java/com/android/tools/r8/DexRoundTrip.java
@@ -5,8 +5,8 @@
 
 import com.android.tools.r8.utils.AndroidApp;
 import com.android.tools.r8.utils.AndroidAppConsumers;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.InternalOptions;
+import com.android.tools.r8.utils.internal.FileUtils;
 import java.nio.file.Path;
 import java.nio.file.Paths;
 
diff --git a/src/main/java/com/android/tools/r8/DirectoryClassFileProvider.java b/src/main/java/com/android/tools/r8/DirectoryClassFileProvider.java
index 53f15ba..bee5da7 100644
--- a/src/main/java/com/android/tools/r8/DirectoryClassFileProvider.java
+++ b/src/main/java/com/android/tools/r8/DirectoryClassFileProvider.java
@@ -3,8 +3,8 @@
 // BSD-style license that can be found in the LICENSE file.
 package com.android.tools.r8;
 
-import static com.android.tools.r8.utils.FileUtils.CLASS_EXTENSION;
-import static com.android.tools.r8.utils.FileUtils.isClassFile;
+import static com.android.tools.r8.utils.internal.FileUtils.CLASS_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.isClassFile;
 
 import com.android.tools.r8.ProgramResource.Kind;
 import com.android.tools.r8.keepanno.annotations.KeepForApi;
diff --git a/src/main/java/com/android/tools/r8/ExtractKeepAnnoRulesCommand.java b/src/main/java/com/android/tools/r8/ExtractKeepAnnoRulesCommand.java
index 46d9490..2bf450e 100644
--- a/src/main/java/com/android/tools/r8/ExtractKeepAnnoRulesCommand.java
+++ b/src/main/java/com/android/tools/r8/ExtractKeepAnnoRulesCommand.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.utils.InternalOptions;
 import com.android.tools.r8.utils.Reporter;
 import com.android.tools.r8.utils.StringDiagnostic;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.nio.file.Paths;
 
diff --git a/src/main/java/com/android/tools/r8/ExtractMarker.java b/src/main/java/com/android/tools/r8/ExtractMarker.java
index ac9b7e4..939d516 100644
--- a/src/main/java/com/android/tools/r8/ExtractMarker.java
+++ b/src/main/java/com/android/tools/r8/ExtractMarker.java
@@ -3,7 +3,7 @@
 // BSD-style license that can be found in the LICENSE file.
 package com.android.tools.r8;
 
-import static com.android.tools.r8.utils.StringUtils.quote;
+import static com.android.tools.r8.utils.internal.StringUtils.quote;
 
 import com.android.tools.r8.dex.ApplicationReader;
 import com.android.tools.r8.dex.Marker;
diff --git a/src/main/java/com/android/tools/r8/ExtractR8Rules.java b/src/main/java/com/android/tools/r8/ExtractR8Rules.java
index b7896ee..29d2c98 100644
--- a/src/main/java/com/android/tools/r8/ExtractR8Rules.java
+++ b/src/main/java/com/android/tools/r8/ExtractR8Rules.java
@@ -11,9 +11,9 @@
 import com.android.tools.r8.utils.ExceptionUtils;
 import com.android.tools.r8.utils.InternalOptions;
 import com.android.tools.r8.utils.Reporter;
-import com.android.tools.r8.utils.internal.SemanticVersion;
 import com.android.tools.r8.utils.SemanticVersionUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.SemanticVersion;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.io.UncheckedIOException;
 import java.util.function.Supplier;
diff --git a/src/main/java/com/android/tools/r8/ExtractR8RulesCommand.java b/src/main/java/com/android/tools/r8/ExtractR8RulesCommand.java
index 29c6cb7..be23d8d 100644
--- a/src/main/java/com/android/tools/r8/ExtractR8RulesCommand.java
+++ b/src/main/java/com/android/tools/r8/ExtractR8RulesCommand.java
@@ -10,9 +10,9 @@
 import com.android.tools.r8.utils.AndroidApp;
 import com.android.tools.r8.utils.InternalOptions;
 import com.android.tools.r8.utils.Reporter;
-import com.android.tools.r8.utils.internal.SemanticVersion;
 import com.android.tools.r8.utils.StringDiagnostic;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.SemanticVersion;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.nio.file.Paths;
 
diff --git a/src/main/java/com/android/tools/r8/GlobalSyntheticsGenerator.java b/src/main/java/com/android/tools/r8/GlobalSyntheticsGenerator.java
index 65cbd64..0ae18a8 100644
--- a/src/main/java/com/android/tools/r8/GlobalSyntheticsGenerator.java
+++ b/src/main/java/com/android/tools/r8/GlobalSyntheticsGenerator.java
@@ -57,8 +57,8 @@
 import com.android.tools.r8.utils.InternalOptions;
 import com.android.tools.r8.utils.ReachabilitySensitiveValue;
 import com.android.tools.r8.utils.SelfRetraceTest;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.ThreadUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.timing.Timing;
 import com.google.common.collect.ImmutableSet;
 import java.io.IOException;
diff --git a/src/main/java/com/android/tools/r8/GlobalSyntheticsGeneratorCommandParser.java b/src/main/java/com/android/tools/r8/GlobalSyntheticsGeneratorCommandParser.java
index 3f80581..1bb711c 100644
--- a/src/main/java/com/android/tools/r8/GlobalSyntheticsGeneratorCommandParser.java
+++ b/src/main/java/com/android/tools/r8/GlobalSyntheticsGeneratorCommandParser.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.utils.FlagFile;
 import com.android.tools.r8.utils.StringDiagnostic;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 import java.nio.file.Path;
diff --git a/src/main/java/com/android/tools/r8/JdkClassFileProvider.java b/src/main/java/com/android/tools/r8/JdkClassFileProvider.java
index 22e2a15..30222fe 100644
--- a/src/main/java/com/android/tools/r8/JdkClassFileProvider.java
+++ b/src/main/java/com/android/tools/r8/JdkClassFileProvider.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.origin.PathOrigin;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.FileUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import java.io.Closeable;
 import java.io.IOException;
 import java.net.URI;
diff --git a/src/main/java/com/android/tools/r8/L8.java b/src/main/java/com/android/tools/r8/L8.java
index 6f0143b..f2d2fd9 100644
--- a/src/main/java/com/android/tools/r8/L8.java
+++ b/src/main/java/com/android/tools/r8/L8.java
@@ -27,8 +27,8 @@
 import com.android.tools.r8.utils.ExceptionUtils;
 import com.android.tools.r8.utils.InternalOptions;
 import com.android.tools.r8.utils.SelfRetraceTest;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.ThreadUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.timing.Timing;
 import java.io.IOException;
 import java.util.concurrent.ExecutionException;
diff --git a/src/main/java/com/android/tools/r8/L8CommandParser.java b/src/main/java/com/android/tools/r8/L8CommandParser.java
index a2a519b..a06ce99 100644
--- a/src/main/java/com/android/tools/r8/L8CommandParser.java
+++ b/src/main/java/com/android/tools/r8/L8CommandParser.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.profile.art.ArtProfileProviderUtils;
 import com.android.tools.r8.utils.FlagFile;
 import com.android.tools.r8.utils.StringDiagnostic;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 import java.nio.file.Path;
diff --git a/src/main/java/com/android/tools/r8/ParseFlagPrinter.java b/src/main/java/com/android/tools/r8/ParseFlagPrinter.java
index cc35672..58d3fec 100644
--- a/src/main/java/com/android/tools/r8/ParseFlagPrinter.java
+++ b/src/main/java/com/android/tools/r8/ParseFlagPrinter.java
@@ -4,7 +4,7 @@
 package com.android.tools.r8;
 
 import com.android.tools.r8.keepanno.annotations.KeepForApi;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.ArrayList;
 import java.util.List;
 
diff --git a/src/main/java/com/android/tools/r8/R8.java b/src/main/java/com/android/tools/r8/R8.java
index 163e4a1..6a9b637 100644
--- a/src/main/java/com/android/tools/r8/R8.java
+++ b/src/main/java/com/android/tools/r8/R8.java
@@ -121,9 +121,9 @@
 import com.android.tools.r8.utils.Reporter;
 import com.android.tools.r8.utils.ResourceShrinkerUtils;
 import com.android.tools.r8.utils.SelfRetraceTest;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.ThreadUtils;
 import com.android.tools.r8.utils.internal.AssertionUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.timing.Timing;
 import com.android.tools.r8.verticalclassmerging.VerticalClassMerger;
 import com.google.common.collect.Iterables;
diff --git a/src/main/java/com/android/tools/r8/R8Command.java b/src/main/java/com/android/tools/r8/R8Command.java
index 819f400..064102c 100644
--- a/src/main/java/com/android/tools/r8/R8Command.java
+++ b/src/main/java/com/android/tools/r8/R8Command.java
@@ -51,11 +51,9 @@
 import com.android.tools.r8.utils.AndroidApp;
 import com.android.tools.r8.utils.ArchiveResourceProvider;
 import com.android.tools.r8.utils.AssertionConfigurationWithDefault;
-import com.android.tools.r8.utils.internal.Box;
 import com.android.tools.r8.utils.DumpInputFlags;
 import com.android.tools.r8.utils.EmbeddedRulesExtractor;
 import com.android.tools.r8.utils.ExceptionDiagnostic;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.InternalOptions;
 import com.android.tools.r8.utils.InternalOptions.DesugarState;
 import com.android.tools.r8.utils.InternalOptions.HorizontalClassMergerOptions;
@@ -68,13 +66,15 @@
 import com.android.tools.r8.utils.ProgramResourceProviderUtils;
 import com.android.tools.r8.utils.ProgramResourceUtils;
 import com.android.tools.r8.utils.Reporter;
-import com.android.tools.r8.utils.internal.SemanticVersion;
 import com.android.tools.r8.utils.SemanticVersionUtils;
 import com.android.tools.r8.utils.SetUtils;
 import com.android.tools.r8.utils.StringDiagnostic;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.SystemPropertyUtils;
 import com.android.tools.r8.utils.ThreadUtils;
+import com.android.tools.r8.utils.internal.Box;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.SemanticVersion;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Path;
 import java.nio.file.Paths;
diff --git a/src/main/java/com/android/tools/r8/R8CommandParser.java b/src/main/java/com/android/tools/r8/R8CommandParser.java
index 3d55a6c..5235ffc 100644
--- a/src/main/java/com/android/tools/r8/R8CommandParser.java
+++ b/src/main/java/com/android/tools/r8/R8CommandParser.java
@@ -15,12 +15,12 @@
 import com.android.tools.r8.profile.art.ArtProfileProviderUtils;
 import com.android.tools.r8.profile.startup.StartupProfileProviderUtils;
 import com.android.tools.r8.utils.ArchiveResourceProvider;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.FlagFile;
 import com.android.tools.r8.utils.MapIdTemplateProvider;
 import com.android.tools.r8.utils.SourceFileTemplateProvider;
 import com.android.tools.r8.utils.StringDiagnostic;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 import java.io.File;
diff --git a/src/main/java/com/android/tools/r8/ReadMainDexList.java b/src/main/java/com/android/tools/r8/ReadMainDexList.java
index 4061e68..f62d893 100644
--- a/src/main/java/com/android/tools/r8/ReadMainDexList.java
+++ b/src/main/java/com/android/tools/r8/ReadMainDexList.java
@@ -4,8 +4,8 @@
 package com.android.tools.r8;
 
 import com.android.tools.r8.naming.ClassNameMapper;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.Iterators;
 import java.nio.file.Path;
 import java.nio.file.Paths;
diff --git a/src/main/java/com/android/tools/r8/StringResource.java b/src/main/java/com/android/tools/r8/StringResource.java
index 4d097e0..bd4d506 100644
--- a/src/main/java/com/android/tools/r8/StringResource.java
+++ b/src/main/java/com/android/tools/r8/StringResource.java
@@ -5,7 +5,7 @@
 
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.origin.PathOrigin;
-import com.android.tools.r8.utils.FileUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import java.io.IOException;
 import java.nio.charset.Charset;
 import java.nio.charset.StandardCharsets;
diff --git a/src/main/java/com/android/tools/r8/androidapi/AndroidApiModelingOptions.java b/src/main/java/com/android/tools/r8/androidapi/AndroidApiModelingOptions.java
index 6c61415..ef5e315 100644
--- a/src/main/java/com/android/tools/r8/androidapi/AndroidApiModelingOptions.java
+++ b/src/main/java/com/android/tools/r8/androidapi/AndroidApiModelingOptions.java
@@ -14,8 +14,8 @@
 import com.android.tools.r8.references.MethodReference;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.InternalOptions;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.ZipUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Paths;
 import java.util.HashMap;
 import java.util.Map;
diff --git a/src/main/java/com/android/tools/r8/cf/CfCodePrinter.java b/src/main/java/com/android/tools/r8/cf/CfCodePrinter.java
index 1f98236..3d13816 100644
--- a/src/main/java/com/android/tools/r8/cf/CfCodePrinter.java
+++ b/src/main/java/com/android/tools/r8/cf/CfCodePrinter.java
@@ -3,7 +3,7 @@
 // BSD-style license that can be found in the LICENSE file.
 package com.android.tools.r8.cf;
 
-import static com.android.tools.r8.utils.StringUtils.join;
+import static com.android.tools.r8.utils.internal.StringUtils.join;
 
 import com.android.tools.r8.cf.code.CfArithmeticBinop;
 import com.android.tools.r8.cf.code.CfArrayLength;
@@ -64,8 +64,8 @@
 import com.android.tools.r8.ir.code.NumberConversionType;
 import com.android.tools.r8.ir.code.NumericType;
 import com.android.tools.r8.ir.code.ValueType;
-import com.android.tools.r8.utils.StringUtils;
-import com.android.tools.r8.utils.StringUtils.BraceType;
+import com.android.tools.r8.utils.internal.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils.BraceType;
 import com.android.tools.r8.utils.internal.exceptions.Unimplemented;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import com.google.common.collect.ImmutableList;
diff --git a/src/main/java/com/android/tools/r8/cf/CfPrinter.java b/src/main/java/com/android/tools/r8/cf/CfPrinter.java
index 6133f8e..cffd296 100644
--- a/src/main/java/com/android/tools/r8/cf/CfPrinter.java
+++ b/src/main/java/com/android/tools/r8/cf/CfPrinter.java
@@ -76,7 +76,7 @@
 import com.android.tools.r8.ir.code.ValueType;
 import com.android.tools.r8.utils.DescriptorUtils;
 import com.android.tools.r8.utils.RetracerForCodePrinting;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import it.unimi.dsi.fastutil.ints.IntList;
 import it.unimi.dsi.fastutil.objects.Reference2IntMap;
diff --git a/src/main/java/com/android/tools/r8/compatproguard/CompatProguard.java b/src/main/java/com/android/tools/r8/compatproguard/CompatProguard.java
index 5a2fa56..08bd917 100644
--- a/src/main/java/com/android/tools/r8/compatproguard/CompatProguard.java
+++ b/src/main/java/com/android/tools/r8/compatproguard/CompatProguard.java
@@ -16,9 +16,9 @@
 import com.android.tools.r8.errors.CompilationError;
 import com.android.tools.r8.origin.CommandLineOrigin;
 import com.android.tools.r8.utils.ExceptionUtils;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.MapIdTemplateProvider;
 import com.android.tools.r8.utils.SourceFileTemplateProvider;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Path;
 import java.nio.file.Paths;
diff --git a/src/main/java/com/android/tools/r8/debuginfo/DebugRepresentation.java b/src/main/java/com/android/tools/r8/debuginfo/DebugRepresentation.java
index fea0740..3ed60c0 100644
--- a/src/main/java/com/android/tools/r8/debuginfo/DebugRepresentation.java
+++ b/src/main/java/com/android/tools/r8/debuginfo/DebugRepresentation.java
@@ -15,8 +15,8 @@
 import com.android.tools.r8.utils.CollectionUtils;
 import com.android.tools.r8.utils.InternalOptions;
 import com.android.tools.r8.utils.LebUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.internal.IterableUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.positions.LineNumberOptimizer;
 import com.android.tools.r8.utils.positions.PositionUtils;
 import it.unimi.dsi.fastutil.ints.Int2ReferenceAVLTreeMap;
diff --git a/src/main/java/com/android/tools/r8/dex/DexReader.java b/src/main/java/com/android/tools/r8/dex/DexReader.java
index 87829fe..3284e96 100644
--- a/src/main/java/com/android/tools/r8/dex/DexReader.java
+++ b/src/main/java/com/android/tools/r8/dex/DexReader.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.errors.CompilationError;
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.utils.DexVersion;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.nio.BufferUnderflowException;
 import java.nio.ByteOrder;
diff --git a/src/main/java/com/android/tools/r8/dex/Marker.java b/src/main/java/com/android/tools/r8/dex/Marker.java
index 1b03ca6..9004abe 100644
--- a/src/main/java/com/android/tools/r8/dex/Marker.java
+++ b/src/main/java/com/android/tools/r8/dex/Marker.java
@@ -6,7 +6,7 @@
 import com.android.tools.r8.CompilationMode;
 import com.android.tools.r8.graph.DexItemFactory;
 import com.android.tools.r8.graph.DexString;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.gson.JsonArray;
 import com.google.gson.JsonElement;
 import com.google.gson.JsonObject;
diff --git a/src/main/java/com/android/tools/r8/dex/ResourceAdapter.java b/src/main/java/com/android/tools/r8/dex/ResourceAdapter.java
index d15b11f..a6f67b2 100644
--- a/src/main/java/com/android/tools/r8/dex/ResourceAdapter.java
+++ b/src/main/java/com/android/tools/r8/dex/ResourceAdapter.java
@@ -20,10 +20,10 @@
 import com.android.tools.r8.shaking.ProguardPathFilter;
 import com.android.tools.r8.utils.DescriptorUtils;
 import com.android.tools.r8.utils.ExceptionDiagnostic;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.InternalOptions;
 import com.android.tools.r8.utils.StringDiagnostic;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import com.google.common.io.ByteStreams;
 import it.unimi.dsi.fastutil.ints.IntArrayList;
diff --git a/src/main/java/com/android/tools/r8/dex/VirtualFile.java b/src/main/java/com/android/tools/r8/dex/VirtualFile.java
index 9dde8fa..7301877 100644
--- a/src/main/java/com/android/tools/r8/dex/VirtualFile.java
+++ b/src/main/java/com/android/tools/r8/dex/VirtualFile.java
@@ -19,10 +19,10 @@
 import com.android.tools.r8.graph.DexType;
 import com.android.tools.r8.graph.ObjectToOffsetMapping;
 import com.android.tools.r8.profile.startup.profile.StartupProfile;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.InternalOptions;
 import com.android.tools.r8.utils.Reporter;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.timing.Timing;
 import com.google.common.collect.Sets;
 import com.google.common.hash.HashCode;
diff --git a/src/main/java/com/android/tools/r8/dex/code/DexConst.java b/src/main/java/com/android/tools/r8/dex/code/DexConst.java
index c47c264..6f5d6cc 100644
--- a/src/main/java/com/android/tools/r8/dex/code/DexConst.java
+++ b/src/main/java/com/android/tools/r8/dex/code/DexConst.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.ir.code.SingleConstant;
 import com.android.tools.r8.ir.conversion.IRBuilder;
 import com.android.tools.r8.utils.RetracerForCodePrinting;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 
 public class DexConst extends DexFormat31i implements SingleConstant {
 
diff --git a/src/main/java/com/android/tools/r8/dex/code/DexConst16.java b/src/main/java/com/android/tools/r8/dex/code/DexConst16.java
index d676e03..59c0968 100644
--- a/src/main/java/com/android/tools/r8/dex/code/DexConst16.java
+++ b/src/main/java/com/android/tools/r8/dex/code/DexConst16.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.ir.code.SingleConstant;
 import com.android.tools.r8.ir.conversion.IRBuilder;
 import com.android.tools.r8.utils.RetracerForCodePrinting;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 
 public class DexConst16 extends DexFormat21s implements SingleConstant {
 
diff --git a/src/main/java/com/android/tools/r8/dex/code/DexConst4.java b/src/main/java/com/android/tools/r8/dex/code/DexConst4.java
index 6a68369..f44b240 100644
--- a/src/main/java/com/android/tools/r8/dex/code/DexConst4.java
+++ b/src/main/java/com/android/tools/r8/dex/code/DexConst4.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.ir.code.SingleConstant;
 import com.android.tools.r8.ir.conversion.IRBuilder;
 import com.android.tools.r8.utils.RetracerForCodePrinting;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 
 public class DexConst4 extends DexFormat11n implements SingleConstant {
 
diff --git a/src/main/java/com/android/tools/r8/dex/code/DexConstHigh16.java b/src/main/java/com/android/tools/r8/dex/code/DexConstHigh16.java
index 82a6aa3..a16ce60 100644
--- a/src/main/java/com/android/tools/r8/dex/code/DexConstHigh16.java
+++ b/src/main/java/com/android/tools/r8/dex/code/DexConstHigh16.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.ir.code.SingleConstant;
 import com.android.tools.r8.ir.conversion.IRBuilder;
 import com.android.tools.r8.utils.RetracerForCodePrinting;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 
 public class DexConstHigh16 extends DexFormat21h implements SingleConstant {
 
diff --git a/src/main/java/com/android/tools/r8/dex/code/DexConstWide.java b/src/main/java/com/android/tools/r8/dex/code/DexConstWide.java
index 899e221..8dafee7 100644
--- a/src/main/java/com/android/tools/r8/dex/code/DexConstWide.java
+++ b/src/main/java/com/android/tools/r8/dex/code/DexConstWide.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.ir.code.WideConstant;
 import com.android.tools.r8.ir.conversion.IRBuilder;
 import com.android.tools.r8.utils.RetracerForCodePrinting;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 
 public class DexConstWide extends DexFormat51l implements WideConstant {
 
diff --git a/src/main/java/com/android/tools/r8/dex/code/DexConstWide16.java b/src/main/java/com/android/tools/r8/dex/code/DexConstWide16.java
index 2cd5ae3..95eac84 100644
--- a/src/main/java/com/android/tools/r8/dex/code/DexConstWide16.java
+++ b/src/main/java/com/android/tools/r8/dex/code/DexConstWide16.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.ir.code.WideConstant;
 import com.android.tools.r8.ir.conversion.IRBuilder;
 import com.android.tools.r8.utils.RetracerForCodePrinting;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 
 public class DexConstWide16 extends DexFormat21s implements WideConstant {
 
diff --git a/src/main/java/com/android/tools/r8/dex/code/DexConstWide32.java b/src/main/java/com/android/tools/r8/dex/code/DexConstWide32.java
index 9797a19..bbbe0c8 100644
--- a/src/main/java/com/android/tools/r8/dex/code/DexConstWide32.java
+++ b/src/main/java/com/android/tools/r8/dex/code/DexConstWide32.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.ir.code.WideConstant;
 import com.android.tools.r8.ir.conversion.IRBuilder;
 import com.android.tools.r8.utils.RetracerForCodePrinting;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 
 public class DexConstWide32 extends DexFormat31i implements WideConstant {
 
diff --git a/src/main/java/com/android/tools/r8/dex/code/DexConstWideHigh16.java b/src/main/java/com/android/tools/r8/dex/code/DexConstWideHigh16.java
index 93b7f34..2df7ee1 100644
--- a/src/main/java/com/android/tools/r8/dex/code/DexConstWideHigh16.java
+++ b/src/main/java/com/android/tools/r8/dex/code/DexConstWideHigh16.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.ir.code.WideConstant;
 import com.android.tools.r8.ir.conversion.IRBuilder;
 import com.android.tools.r8.utils.RetracerForCodePrinting;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 
 public class DexConstWideHigh16 extends DexFormat21h implements WideConstant {
 
diff --git a/src/main/java/com/android/tools/r8/dex/code/DexFillArrayDataPayload.java b/src/main/java/com/android/tools/r8/dex/code/DexFillArrayDataPayload.java
index ceaaa09..9a1789e 100644
--- a/src/main/java/com/android/tools/r8/dex/code/DexFillArrayDataPayload.java
+++ b/src/main/java/com/android/tools/r8/dex/code/DexFillArrayDataPayload.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.ir.conversion.IRBuilder;
 import com.android.tools.r8.ir.conversion.LensCodeRewriterUtils;
 import com.android.tools.r8.utils.RetracerForCodePrinting;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.structural.CompareToVisitor;
 import com.android.tools.r8.utils.structural.HashingVisitor;
 import com.android.tools.r8.utils.structural.StructuralSpecification;
diff --git a/src/main/java/com/android/tools/r8/dex/code/DexFormat21s.java b/src/main/java/com/android/tools/r8/dex/code/DexFormat21s.java
index 254efee..2f30aae 100644
--- a/src/main/java/com/android/tools/r8/dex/code/DexFormat21s.java
+++ b/src/main/java/com/android/tools/r8/dex/code/DexFormat21s.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.graph.lens.GraphLens;
 import com.android.tools.r8.ir.conversion.LensCodeRewriterUtils;
 import com.android.tools.r8.utils.RetracerForCodePrinting;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.structural.CompareToVisitor;
 import com.android.tools.r8.utils.structural.HashingVisitor;
 import com.android.tools.r8.utils.structural.StructuralSpecification;
diff --git a/src/main/java/com/android/tools/r8/dex/code/DexFormat22b.java b/src/main/java/com/android/tools/r8/dex/code/DexFormat22b.java
index 6334bc5..5b53898 100644
--- a/src/main/java/com/android/tools/r8/dex/code/DexFormat22b.java
+++ b/src/main/java/com/android/tools/r8/dex/code/DexFormat22b.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.graph.lens.GraphLens;
 import com.android.tools.r8.ir.conversion.LensCodeRewriterUtils;
 import com.android.tools.r8.utils.RetracerForCodePrinting;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.structural.CompareToVisitor;
 import com.android.tools.r8.utils.structural.HashingVisitor;
 import com.android.tools.r8.utils.structural.StructuralSpecification;
diff --git a/src/main/java/com/android/tools/r8/dex/code/DexFormat22s.java b/src/main/java/com/android/tools/r8/dex/code/DexFormat22s.java
index f01a75b4..2cf9231 100644
--- a/src/main/java/com/android/tools/r8/dex/code/DexFormat22s.java
+++ b/src/main/java/com/android/tools/r8/dex/code/DexFormat22s.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.graph.lens.GraphLens;
 import com.android.tools.r8.ir.conversion.LensCodeRewriterUtils;
 import com.android.tools.r8.utils.RetracerForCodePrinting;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.structural.CompareToVisitor;
 import com.android.tools.r8.utils.structural.HashingVisitor;
 import com.android.tools.r8.utils.structural.StructuralSpecification;
diff --git a/src/main/java/com/android/tools/r8/dex/code/DexInstruction.java b/src/main/java/com/android/tools/r8/dex/code/DexInstruction.java
index ea11bb3..5e342a5 100644
--- a/src/main/java/com/android/tools/r8/dex/code/DexInstruction.java
+++ b/src/main/java/com/android/tools/r8/dex/code/DexInstruction.java
@@ -19,7 +19,7 @@
 import com.android.tools.r8.ir.conversion.IRBuilder;
 import com.android.tools.r8.ir.conversion.LensCodeRewriterUtils;
 import com.android.tools.r8.utils.RetracerForCodePrinting;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import com.android.tools.r8.utils.structural.CompareToVisitor;
 import com.android.tools.r8.utils.structural.Equatable;
diff --git a/src/main/java/com/android/tools/r8/dex/code/DexPackedSwitchPayload.java b/src/main/java/com/android/tools/r8/dex/code/DexPackedSwitchPayload.java
index 056efc7..7be3695 100644
--- a/src/main/java/com/android/tools/r8/dex/code/DexPackedSwitchPayload.java
+++ b/src/main/java/com/android/tools/r8/dex/code/DexPackedSwitchPayload.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.graph.lens.GraphLens;
 import com.android.tools.r8.ir.conversion.LensCodeRewriterUtils;
 import com.android.tools.r8.utils.RetracerForCodePrinting;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.structural.CompareToVisitor;
 import com.android.tools.r8.utils.structural.HashingVisitor;
 import com.android.tools.r8.utils.structural.StructuralSpecification;
diff --git a/src/main/java/com/android/tools/r8/dex/code/DexSparseSwitchPayload.java b/src/main/java/com/android/tools/r8/dex/code/DexSparseSwitchPayload.java
index 0738430..1b440e6 100644
--- a/src/main/java/com/android/tools/r8/dex/code/DexSparseSwitchPayload.java
+++ b/src/main/java/com/android/tools/r8/dex/code/DexSparseSwitchPayload.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.graph.lens.GraphLens;
 import com.android.tools.r8.ir.conversion.LensCodeRewriterUtils;
 import com.android.tools.r8.utils.RetracerForCodePrinting;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.structural.CompareToVisitor;
 import com.android.tools.r8.utils.structural.HashingVisitor;
 import com.android.tools.r8.utils.structural.StructuralSpecification;
diff --git a/src/main/java/com/android/tools/r8/dump/CompilerDump.java b/src/main/java/com/android/tools/r8/dump/CompilerDump.java
index 926846a..c9bb6b3 100644
--- a/src/main/java/com/android/tools/r8/dump/CompilerDump.java
+++ b/src/main/java/com/android/tools/r8/dump/CompilerDump.java
@@ -6,8 +6,8 @@
 import static com.android.tools.r8.utils.AndroidApp.dumpR8ExcludeFileName;
 import static com.android.tools.r8.utils.AndroidApp.dumpR8IncludeFileName;
 
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.ZipUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import java.io.BufferedReader;
 import java.io.IOException;
 import java.nio.file.Files;
diff --git a/src/main/java/com/android/tools/r8/dump/DumpOptions.java b/src/main/java/com/android/tools/r8/dump/DumpOptions.java
index 510ae33..10dc346 100644
--- a/src/main/java/com/android/tools/r8/dump/DumpOptions.java
+++ b/src/main/java/com/android/tools/r8/dump/DumpOptions.java
@@ -16,8 +16,8 @@
 import com.android.tools.r8.shaking.ProguardConfigurationRule;
 import com.android.tools.r8.startup.StartupProfileProvider;
 import com.android.tools.r8.utils.InternalOptions.DesugarState;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.ThreadUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.HashMap;
diff --git a/src/main/java/com/android/tools/r8/errors/DuplicateTypesDiagnostic.java b/src/main/java/com/android/tools/r8/errors/DuplicateTypesDiagnostic.java
index dde2df2..45eb089 100644
--- a/src/main/java/com/android/tools/r8/errors/DuplicateTypesDiagnostic.java
+++ b/src/main/java/com/android/tools/r8/errors/DuplicateTypesDiagnostic.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.position.Position;
 import com.android.tools.r8.references.ClassReference;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Collection;
 
 @KeepForApi
diff --git a/src/main/java/com/android/tools/r8/errors/EmptyMemberRulesToDefaultInitRuleConversionDiagnostic.java b/src/main/java/com/android/tools/r8/errors/EmptyMemberRulesToDefaultInitRuleConversionDiagnostic.java
index 9a441ce..4315bec 100644
--- a/src/main/java/com/android/tools/r8/errors/EmptyMemberRulesToDefaultInitRuleConversionDiagnostic.java
+++ b/src/main/java/com/android/tools/r8/errors/EmptyMemberRulesToDefaultInitRuleConversionDiagnostic.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.position.Position;
 import com.android.tools.r8.shaking.ProguardConfigurationRule;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 
 @KeepForApi
 public class EmptyMemberRulesToDefaultInitRuleConversionDiagnostic implements Diagnostic {
diff --git a/src/main/java/com/android/tools/r8/errors/InlinableStaticFinalFieldPreconditionDiagnostic.java b/src/main/java/com/android/tools/r8/errors/InlinableStaticFinalFieldPreconditionDiagnostic.java
index 833d7b6..38c5da1 100644
--- a/src/main/java/com/android/tools/r8/errors/InlinableStaticFinalFieldPreconditionDiagnostic.java
+++ b/src/main/java/com/android/tools/r8/errors/InlinableStaticFinalFieldPreconditionDiagnostic.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.shaking.ProguardIfRule;
 import com.android.tools.r8.utils.FieldReferenceUtils;
 import com.android.tools.r8.utils.ListUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Collection;
 import java.util.List;
 
diff --git a/src/main/java/com/android/tools/r8/errors/InvalidLibrarySuperclassDiagnostic.java b/src/main/java/com/android/tools/r8/errors/InvalidLibrarySuperclassDiagnostic.java
index d120176..b472134 100644
--- a/src/main/java/com/android/tools/r8/errors/InvalidLibrarySuperclassDiagnostic.java
+++ b/src/main/java/com/android/tools/r8/errors/InvalidLibrarySuperclassDiagnostic.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.position.Position;
 import com.android.tools.r8.references.ClassReference;
 import com.android.tools.r8.references.MethodReference;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 
 /**
diff --git a/src/main/java/com/android/tools/r8/graph/AppServices.java b/src/main/java/com/android/tools/r8/graph/AppServices.java
index d59ccd6..019c0de 100644
--- a/src/main/java/com/android/tools/r8/graph/AppServices.java
+++ b/src/main/java/com/android/tools/r8/graph/AppServices.java
@@ -19,7 +19,7 @@
 import com.android.tools.r8.utils.DescriptorUtils;
 import com.android.tools.r8.utils.InternalOptions;
 import com.android.tools.r8.utils.StringDiagnostic;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.timing.Timing;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
diff --git a/src/main/java/com/android/tools/r8/graph/AssemblyWriter.java b/src/main/java/com/android/tools/r8/graph/AssemblyWriter.java
index ed52081..5739938 100644
--- a/src/main/java/com/android/tools/r8/graph/AssemblyWriter.java
+++ b/src/main/java/com/android/tools/r8/graph/AssemblyWriter.java
@@ -3,7 +3,7 @@
 // BSD-style license that can be found in the LICENSE file.
 package com.android.tools.r8.graph;
 
-import static com.android.tools.r8.utils.StringUtils.LINE_SEPARATOR;
+import static com.android.tools.r8.utils.internal.StringUtils.LINE_SEPARATOR;
 
 import com.android.tools.r8.ClassFileConsumer;
 import com.android.tools.r8.contexts.CompilationContext;
@@ -21,8 +21,8 @@
 import com.android.tools.r8.synthesis.SyntheticItems.GlobalSyntheticsStrategy;
 import com.android.tools.r8.utils.InternalOptions;
 import com.android.tools.r8.utils.RetracerForCodePrinting;
-import com.android.tools.r8.utils.StringUtils;
-import com.android.tools.r8.utils.StringUtils.BraceType;
+import com.android.tools.r8.utils.internal.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils.BraceType;
 import com.android.tools.r8.utils.timing.Timing;
 import java.io.BufferedReader;
 import java.io.PrintStream;
diff --git a/src/main/java/com/android/tools/r8/graph/CfCodeStackMapValidatingException.java b/src/main/java/com/android/tools/r8/graph/CfCodeStackMapValidatingException.java
index ec6da19..6d8a4ae 100644
--- a/src/main/java/com/android/tools/r8/graph/CfCodeStackMapValidatingException.java
+++ b/src/main/java/com/android/tools/r8/graph/CfCodeStackMapValidatingException.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.cf.code.CfInstruction;
 import com.android.tools.r8.cf.code.CfTryCatch;
 import com.android.tools.r8.errors.CfCodeDiagnostics;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 
 public class CfCodeStackMapValidatingException {
 
diff --git a/src/main/java/com/android/tools/r8/graph/DexCode.java b/src/main/java/com/android/tools/r8/graph/DexCode.java
index 41ca267..04e592d 100644
--- a/src/main/java/com/android/tools/r8/graph/DexCode.java
+++ b/src/main/java/com/android/tools/r8/graph/DexCode.java
@@ -41,8 +41,8 @@
 import com.android.tools.r8.utils.DexDebugUtils.PositionInfo;
 import com.android.tools.r8.utils.InternalOptions;
 import com.android.tools.r8.utils.RetracerForCodePrinting;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.internal.ArrayUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.structural.Equatable;
 import com.android.tools.r8.utils.structural.HashCodeVisitor;
 import com.android.tools.r8.utils.structural.HashingVisitor;
diff --git a/src/main/java/com/android/tools/r8/graph/DexDebugEntry.java b/src/main/java/com/android/tools/r8/graph/DexDebugEntry.java
index 6679383..2e6ca73 100644
--- a/src/main/java/com/android/tools/r8/graph/DexDebugEntry.java
+++ b/src/main/java/com/android/tools/r8/graph/DexDebugEntry.java
@@ -4,7 +4,7 @@
 package com.android.tools.r8.graph;
 
 import com.android.tools.r8.ir.code.Position;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableMap;
 import java.util.Map;
 import java.util.SortedSet;
diff --git a/src/main/java/com/android/tools/r8/graph/DexDebugInfo.java b/src/main/java/com/android/tools/r8/graph/DexDebugInfo.java
index 874dcbb..abd50b9 100644
--- a/src/main/java/com/android/tools/r8/graph/DexDebugInfo.java
+++ b/src/main/java/com/android/tools/r8/graph/DexDebugInfo.java
@@ -13,9 +13,9 @@
 import com.android.tools.r8.dex.code.DexInstruction;
 import com.android.tools.r8.graph.lens.GraphLens;
 import com.android.tools.r8.utils.LebUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.internal.ArrayUtils;
 import com.android.tools.r8.utils.internal.ObjectUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import com.android.tools.r8.utils.structural.CompareToVisitor;
 import com.android.tools.r8.utils.structural.Equatable;
diff --git a/src/main/java/com/android/tools/r8/graph/DexString.java b/src/main/java/com/android/tools/r8/graph/DexString.java
index 85b6e8f..b0ce7ec 100644
--- a/src/main/java/com/android/tools/r8/graph/DexString.java
+++ b/src/main/java/com/android/tools/r8/graph/DexString.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.DescriptorUtils;
 import com.android.tools.r8.utils.IdentifierUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.ThrowingCharIterator;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import com.android.tools.r8.utils.structural.CompareToVisitor;
diff --git a/src/main/java/com/android/tools/r8/graph/JarClassFileReader.java b/src/main/java/com/android/tools/r8/graph/JarClassFileReader.java
index 5d9547f..63d4cbf 100644
--- a/src/main/java/com/android/tools/r8/graph/JarClassFileReader.java
+++ b/src/main/java/com/android/tools/r8/graph/JarClassFileReader.java
@@ -49,7 +49,7 @@
 import com.android.tools.r8.utils.MethodSignatureEquivalence;
 import com.android.tools.r8.utils.ReachabilitySensitiveValue;
 import com.android.tools.r8.utils.StringDiagnostic;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import com.google.common.base.Equivalence.Wrapper;
 import java.nio.ByteBuffer;
diff --git a/src/main/java/com/android/tools/r8/ir/analysis/framework/intraprocedural/cf/CfBlock.java b/src/main/java/com/android/tools/r8/ir/analysis/framework/intraprocedural/cf/CfBlock.java
index b12e8cb..4489269 100644
--- a/src/main/java/com/android/tools/r8/ir/analysis/framework/intraprocedural/cf/CfBlock.java
+++ b/src/main/java/com/android/tools/r8/ir/analysis/framework/intraprocedural/cf/CfBlock.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.graph.DexType;
 import com.android.tools.r8.utils.InternalOptions;
 import com.android.tools.r8.utils.SetUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.LinkedHashMap;
diff --git a/src/main/java/com/android/tools/r8/ir/analysis/value/objectstate/NonEmptyObjectState.java b/src/main/java/com/android/tools/r8/ir/analysis/value/objectstate/NonEmptyObjectState.java
index cc3f212..84c8bc9 100644
--- a/src/main/java/com/android/tools/r8/ir/analysis/value/objectstate/NonEmptyObjectState.java
+++ b/src/main/java/com/android/tools/r8/ir/analysis/value/objectstate/NonEmptyObjectState.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.ir.analysis.value.UnknownValue;
 import com.android.tools.r8.shaking.AppInfoWithLiveness;
 import com.android.tools.r8.utils.ListUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.ArrayList;
 import java.util.IdentityHashMap;
 import java.util.List;
diff --git a/src/main/java/com/android/tools/r8/ir/code/BasicBlock.java b/src/main/java/com/android/tools/r8/ir/code/BasicBlock.java
index ed1005d..584f32d 100644
--- a/src/main/java/com/android/tools/r8/ir/code/BasicBlock.java
+++ b/src/main/java/com/android/tools/r8/ir/code/BasicBlock.java
@@ -26,9 +26,9 @@
 import com.android.tools.r8.ir.optimize.AffectedValues;
 import com.android.tools.r8.utils.InternalOptions;
 import com.android.tools.r8.utils.ListUtils;
-import com.android.tools.r8.utils.StringUtils;
-import com.android.tools.r8.utils.StringUtils.BraceType;
 import com.android.tools.r8.utils.internal.IterableUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils.BraceType;
 import com.android.tools.r8.utils.internal.TraversalContinuation;
 import com.android.tools.r8.utils.internal.TriFunction;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
diff --git a/src/main/java/com/android/tools/r8/ir/code/Cmp.java b/src/main/java/com/android/tools/r8/ir/code/Cmp.java
index 23fccf6..dc638e3 100644
--- a/src/main/java/com/android/tools/r8/ir/code/Cmp.java
+++ b/src/main/java/com/android/tools/r8/ir/code/Cmp.java
@@ -20,8 +20,8 @@
 import com.android.tools.r8.ir.conversion.CfBuilder;
 import com.android.tools.r8.ir.conversion.DexBuilder;
 import com.android.tools.r8.lightir.LirBuilder;
-import com.android.tools.r8.utils.StringUtils;
-import com.android.tools.r8.utils.StringUtils.BraceType;
+import com.android.tools.r8.utils.internal.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils.BraceType;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 
 public class Cmp extends Binop {
diff --git a/src/main/java/com/android/tools/r8/ir/code/DebugLocalsChange.java b/src/main/java/com/android/tools/r8/ir/code/DebugLocalsChange.java
index cc7ef77..c9cdc19 100644
--- a/src/main/java/com/android/tools/r8/ir/code/DebugLocalsChange.java
+++ b/src/main/java/com/android/tools/r8/ir/code/DebugLocalsChange.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.ir.optimize.Inliner.ConstraintWithTarget;
 import com.android.tools.r8.ir.optimize.InliningConstraints;
 import com.android.tools.r8.lightir.LirBuilder;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import it.unimi.dsi.fastutil.ints.Int2ReferenceMap;
 import it.unimi.dsi.fastutil.ints.Int2ReferenceMap.Entry;
diff --git a/src/main/java/com/android/tools/r8/ir/code/IRCode.java b/src/main/java/com/android/tools/r8/ir/code/IRCode.java
index 742f4a6..fd34163 100644
--- a/src/main/java/com/android/tools/r8/ir/code/IRCode.java
+++ b/src/main/java/com/android/tools/r8/ir/code/IRCode.java
@@ -32,13 +32,13 @@
 import com.android.tools.r8.utils.InternalOptions;
 import com.android.tools.r8.utils.ListUtils;
 import com.android.tools.r8.utils.SetUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.collections.WorkList;
 import com.android.tools.r8.utils.internal.BooleanUtils;
 import com.android.tools.r8.utils.internal.DequeUtils;
 import com.android.tools.r8.utils.internal.IteratorUtils;
 import com.android.tools.r8.utils.internal.LinkedHashSetUtils;
 import com.android.tools.r8.utils.internal.LongUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.TraversalContinuation;
 import com.android.tools.r8.utils.internal.TriFunction;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
diff --git a/src/main/java/com/android/tools/r8/ir/code/Instruction.java b/src/main/java/com/android/tools/r8/ir/code/Instruction.java
index bd86432..d3bec76 100644
--- a/src/main/java/com/android/tools/r8/ir/code/Instruction.java
+++ b/src/main/java/com/android/tools/r8/ir/code/Instruction.java
@@ -34,11 +34,11 @@
 import com.android.tools.r8.ir.regalloc.RegisterAllocator;
 import com.android.tools.r8.lightir.LirBuilder;
 import com.android.tools.r8.shaking.AppInfoWithLiveness;
-import com.android.tools.r8.utils.internal.IntObjPredicate;
 import com.android.tools.r8.utils.InternalOptions;
+import com.android.tools.r8.utils.internal.IntObjPredicate;
 import com.android.tools.r8.utils.internal.LongInterval;
-import com.android.tools.r8.utils.StringUtils;
-import com.android.tools.r8.utils.StringUtils.BraceType;
+import com.android.tools.r8.utils.internal.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils.BraceType;
 import com.android.tools.r8.utils.internal.exceptions.Unimplemented;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import com.google.common.collect.ImmutableSet;
diff --git a/src/main/java/com/android/tools/r8/ir/code/Phi.java b/src/main/java/com/android/tools/r8/ir/code/Phi.java
index 1407724..a365481 100644
--- a/src/main/java/com/android/tools/r8/ir/code/Phi.java
+++ b/src/main/java/com/android/tools/r8/ir/code/Phi.java
@@ -22,11 +22,11 @@
 import com.android.tools.r8.ir.conversion.TypeConstraintResolver;
 import com.android.tools.r8.ir.optimize.AffectedValues;
 import com.android.tools.r8.shaking.AppInfoWithLiveness;
-import com.android.tools.r8.utils.internal.DequeUtils;
 import com.android.tools.r8.utils.ListUtils;
 import com.android.tools.r8.utils.Reporter;
 import com.android.tools.r8.utils.SetUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.DequeUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.Sets;
 import java.util.ArrayList;
 import java.util.Deque;
diff --git a/src/main/java/com/android/tools/r8/ir/desugar/desugaredlibrary/lint/DesugaredMethodsListCommand.java b/src/main/java/com/android/tools/r8/ir/desugar/desugaredlibrary/lint/DesugaredMethodsListCommand.java
index 34978f4..ca7f110 100644
--- a/src/main/java/com/android/tools/r8/ir/desugar/desugaredlibrary/lint/DesugaredMethodsListCommand.java
+++ b/src/main/java/com/android/tools/r8/ir/desugar/desugaredlibrary/lint/DesugaredMethodsListCommand.java
@@ -20,7 +20,7 @@
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.Reporter;
 import com.android.tools.r8.utils.StringDiagnostic;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
diff --git a/src/main/java/com/android/tools/r8/ir/desugar/desugaredlibrary/lint/GenerateDesugaredLibraryLintFiles.java b/src/main/java/com/android/tools/r8/ir/desugar/desugaredlibrary/lint/GenerateDesugaredLibraryLintFiles.java
index b257bc2..4348388 100644
--- a/src/main/java/com/android/tools/r8/ir/desugar/desugaredlibrary/lint/GenerateDesugaredLibraryLintFiles.java
+++ b/src/main/java/com/android/tools/r8/ir/desugar/desugaredlibrary/lint/GenerateDesugaredLibraryLintFiles.java
@@ -14,9 +14,9 @@
 import com.android.tools.r8.ir.desugar.desugaredlibrary.lint.SupportedClasses.MethodAnnotation;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.Reporter;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.File;
 import java.io.IOException;
diff --git a/src/main/java/com/android/tools/r8/ir/desugar/desugaredlibrary/lint/GenerateHtmlDoc.java b/src/main/java/com/android/tools/r8/ir/desugar/desugaredlibrary/lint/GenerateHtmlDoc.java
index 7b3644f..efd14db 100644
--- a/src/main/java/com/android/tools/r8/ir/desugar/desugaredlibrary/lint/GenerateHtmlDoc.java
+++ b/src/main/java/com/android/tools/r8/ir/desugar/desugaredlibrary/lint/GenerateHtmlDoc.java
@@ -24,7 +24,7 @@
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.ListUtils;
 import com.android.tools.r8.utils.Reporter;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.PrintStream;
 import java.nio.file.Files;
diff --git a/src/main/java/com/android/tools/r8/ir/desugar/desugaredlibrary/machinespecification/MachineDesugaredLibrarySpecification.java b/src/main/java/com/android/tools/r8/ir/desugar/desugaredlibrary/machinespecification/MachineDesugaredLibrarySpecification.java
index 8937bcb..4223d7e 100644
--- a/src/main/java/com/android/tools/r8/ir/desugar/desugaredlibrary/machinespecification/MachineDesugaredLibrarySpecification.java
+++ b/src/main/java/com/android/tools/r8/ir/desugar/desugaredlibrary/machinespecification/MachineDesugaredLibrarySpecification.java
@@ -18,7 +18,7 @@
 import com.android.tools.r8.utils.DescriptorUtils;
 import com.android.tools.r8.utils.ListUtils;
 import com.android.tools.r8.utils.internal.SemanticVersion;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.timing.Timing;
 import java.util.List;
 import java.util.Map;
diff --git a/src/main/java/com/android/tools/r8/ir/optimize/enums/LocalEnumUnboxingUtilityClass.java b/src/main/java/com/android/tools/r8/ir/optimize/enums/LocalEnumUnboxingUtilityClass.java
index 09bfc5a..d55d8d6 100644
--- a/src/main/java/com/android/tools/r8/ir/optimize/enums/LocalEnumUnboxingUtilityClass.java
+++ b/src/main/java/com/android/tools/r8/ir/optimize/enums/LocalEnumUnboxingUtilityClass.java
@@ -22,7 +22,7 @@
 import com.android.tools.r8.ir.synthetic.EnumUnboxingCfCodeProvider;
 import com.android.tools.r8.shaking.AppInfoWithLiveness;
 import com.android.tools.r8.synthesis.SyntheticMethodBuilder.SyntheticCodeGenerator;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 
 public class LocalEnumUnboxingUtilityClass extends EnumUnboxingUtilityClass {
 
diff --git a/src/main/java/com/android/tools/r8/ir/optimize/info/OptimizationFeedbackDelayed.java b/src/main/java/com/android/tools/r8/ir/optimize/info/OptimizationFeedbackDelayed.java
index 2542c6c..e327978 100644
--- a/src/main/java/com/android/tools/r8/ir/optimize/info/OptimizationFeedbackDelayed.java
+++ b/src/main/java/com/android/tools/r8/ir/optimize/info/OptimizationFeedbackDelayed.java
@@ -21,8 +21,8 @@
 import com.android.tools.r8.shaking.AppInfoWithLiveness;
 import com.android.tools.r8.shaking.AppInfoWithLivenessModifier;
 import com.android.tools.r8.threading.ThreadingModule;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.internal.IteratorUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.BitSet;
 import java.util.IdentityHashMap;
 import java.util.Map;
diff --git a/src/main/java/com/android/tools/r8/ir/optimize/info/field/NonTrivialInstanceFieldInitializationInfoCollection.java b/src/main/java/com/android/tools/r8/ir/optimize/info/field/NonTrivialInstanceFieldInitializationInfoCollection.java
index 7fa9d04..4e884f2 100644
--- a/src/main/java/com/android/tools/r8/ir/optimize/info/field/NonTrivialInstanceFieldInitializationInfoCollection.java
+++ b/src/main/java/com/android/tools/r8/ir/optimize/info/field/NonTrivialInstanceFieldInitializationInfoCollection.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.graph.lens.GraphLens;
 import com.android.tools.r8.graph.proto.ArgumentInfoCollection;
 import com.android.tools.r8.shaking.AppInfoWithLiveness;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.TreeMap;
diff --git a/src/main/java/com/android/tools/r8/ir/optimize/inliner/WhyAreYouNotInliningReporterImpl.java b/src/main/java/com/android/tools/r8/ir/optimize/inliner/WhyAreYouNotInliningReporterImpl.java
index 857fa35..b793ead 100644
--- a/src/main/java/com/android/tools/r8/ir/optimize/inliner/WhyAreYouNotInliningReporterImpl.java
+++ b/src/main/java/com/android/tools/r8/ir/optimize/inliner/WhyAreYouNotInliningReporterImpl.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.ir.code.InvokeDirect;
 import com.android.tools.r8.ir.optimize.Inliner.Reason;
 import com.android.tools.r8.utils.Reporter;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Set;
 
 class WhyAreYouNotInliningReporterImpl extends WhyAreYouNotInliningReporter {
diff --git a/src/main/java/com/android/tools/r8/ir/optimize/library/primitive/BooleanMethodOptimizer.java b/src/main/java/com/android/tools/r8/ir/optimize/library/primitive/BooleanMethodOptimizer.java
index 395386d..da97c0e 100644
--- a/src/main/java/com/android/tools/r8/ir/optimize/library/primitive/BooleanMethodOptimizer.java
+++ b/src/main/java/com/android/tools/r8/ir/optimize/library/primitive/BooleanMethodOptimizer.java
@@ -18,7 +18,7 @@
 import com.android.tools.r8.ir.code.InvokeMethod;
 import com.android.tools.r8.ir.code.Value;
 import com.android.tools.r8.ir.optimize.AffectedValues;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Set;
 
 public class BooleanMethodOptimizer extends PrimitiveMethodOptimizer {
diff --git a/src/main/java/com/android/tools/r8/ir/optimize/outliner/OutlinerImpl.java b/src/main/java/com/android/tools/r8/ir/optimize/outliner/OutlinerImpl.java
index 08b0d99..4ce6dae 100644
--- a/src/main/java/com/android/tools/r8/ir/optimize/outliner/OutlinerImpl.java
+++ b/src/main/java/com/android/tools/r8/ir/optimize/outliner/OutlinerImpl.java
@@ -75,12 +75,12 @@
 import com.android.tools.r8.utils.InternalOptions;
 import com.android.tools.r8.utils.InternalOptions.OutlineOptions;
 import com.android.tools.r8.utils.ListUtils;
-import com.android.tools.r8.utils.internal.ObjectUtils;
 import com.android.tools.r8.utils.RetracerForCodePrinting;
-import com.android.tools.r8.utils.StringUtils;
-import com.android.tools.r8.utils.StringUtils.BraceType;
 import com.android.tools.r8.utils.ThreadUtils;
 import com.android.tools.r8.utils.collections.ProgramMethodSet;
+import com.android.tools.r8.utils.internal.ObjectUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils.BraceType;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import com.android.tools.r8.utils.timing.Timing;
 import com.google.common.collect.ImmutableList;
diff --git a/src/main/java/com/android/tools/r8/ir/regalloc/LinearScanRegisterAllocator.java b/src/main/java/com/android/tools/r8/ir/regalloc/LinearScanRegisterAllocator.java
index 9492bee..f9ee9a3 100644
--- a/src/main/java/com/android/tools/r8/ir/regalloc/LinearScanRegisterAllocator.java
+++ b/src/main/java/com/android/tools/r8/ir/regalloc/LinearScanRegisterAllocator.java
@@ -48,12 +48,12 @@
 import com.android.tools.r8.utils.InternalOptions;
 import com.android.tools.r8.utils.ListUtils;
 import com.android.tools.r8.utils.SetUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.internal.ArrayUtils;
 import com.android.tools.r8.utils.internal.BooleanUtils;
 import com.android.tools.r8.utils.internal.IntObjPredicate;
 import com.android.tools.r8.utils.internal.IterableUtils;
 import com.android.tools.r8.utils.internal.LinkedHashSetUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import com.android.tools.r8.utils.timing.Timing;
 import com.google.common.collect.HashMultiset;
diff --git a/src/main/java/com/android/tools/r8/kotlin/KotlinMetadataDiagnostic.java b/src/main/java/com/android/tools/r8/kotlin/KotlinMetadataDiagnostic.java
index f166f67..ae2ffb6 100644
--- a/src/main/java/com/android/tools/r8/kotlin/KotlinMetadataDiagnostic.java
+++ b/src/main/java/com/android/tools/r8/kotlin/KotlinMetadataDiagnostic.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.keepanno.annotations.KeepForApi;
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.position.Position;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 
 @KeepForApi
 public class KotlinMetadataDiagnostic implements Diagnostic {
diff --git a/src/main/java/com/android/tools/r8/kotlin/KotlinMetadataWriter.java b/src/main/java/com/android/tools/r8/kotlin/KotlinMetadataWriter.java
index 10e539e..237a877 100644
--- a/src/main/java/com/android/tools/r8/kotlin/KotlinMetadataWriter.java
+++ b/src/main/java/com/android/tools/r8/kotlin/KotlinMetadataWriter.java
@@ -4,11 +4,11 @@
 
 package com.android.tools.r8.kotlin;
 
-import static com.android.tools.r8.utils.StringUtils.LINE_SEPARATOR;
+import static com.android.tools.r8.utils.internal.StringUtils.LINE_SEPARATOR;
 
 import com.android.tools.r8.graph.DexAnnotation;
 import com.android.tools.r8.utils.internal.Action;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import java.io.PrintStream;
 import java.util.Collection;
diff --git a/src/main/java/com/android/tools/r8/kotlin/KotlinSourceDebugExtensionParser.java b/src/main/java/com/android/tools/r8/kotlin/KotlinSourceDebugExtensionParser.java
index d0132ab..e2efac1 100644
--- a/src/main/java/com/android/tools/r8/kotlin/KotlinSourceDebugExtensionParser.java
+++ b/src/main/java/com/android/tools/r8/kotlin/KotlinSourceDebugExtensionParser.java
@@ -6,7 +6,7 @@
 
 import com.android.tools.r8.graph.DexValue.DexValueString;
 import com.android.tools.r8.naming.Range;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.ThrowingConsumer;
 import com.android.tools.r8.utils.internal.collections.SegmentTree;
 import java.io.BufferedReader;
diff --git a/src/main/java/com/android/tools/r8/lightir/LirPrinter.java b/src/main/java/com/android/tools/r8/lightir/LirPrinter.java
index f83abe1..6e0e7b1 100644
--- a/src/main/java/com/android/tools/r8/lightir/LirPrinter.java
+++ b/src/main/java/com/android/tools/r8/lightir/LirPrinter.java
@@ -23,7 +23,7 @@
 import com.android.tools.r8.naming.dexitembasedstring.NameComputationInfo;
 import com.android.tools.r8.utils.internal.IntUtils;
 import com.android.tools.r8.utils.internal.LongUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unimplemented;
 import java.util.Arrays;
 import java.util.List;
diff --git a/src/main/java/com/android/tools/r8/naming/ClassNameMinifier.java b/src/main/java/com/android/tools/r8/naming/ClassNameMinifier.java
index b6e5f92..b030f41 100644
--- a/src/main/java/com/android/tools/r8/naming/ClassNameMinifier.java
+++ b/src/main/java/com/android/tools/r8/naming/ClassNameMinifier.java
@@ -21,7 +21,7 @@
 import com.android.tools.r8.shaking.AppInfoWithLiveness;
 import com.android.tools.r8.utils.DescriptorUtils;
 import com.android.tools.r8.utils.InternalOptions;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.timing.Timing;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.Maps;
diff --git a/src/main/java/com/android/tools/r8/naming/IdentifierNameStringUtils.java b/src/main/java/com/android/tools/r8/naming/IdentifierNameStringUtils.java
index a6124ba..a194cb9 100644
--- a/src/main/java/com/android/tools/r8/naming/IdentifierNameStringUtils.java
+++ b/src/main/java/com/android/tools/r8/naming/IdentifierNameStringUtils.java
@@ -33,7 +33,7 @@
 import com.android.tools.r8.ir.code.NewArrayFilled;
 import com.android.tools.r8.ir.code.Value;
 import com.android.tools.r8.naming.identifiernamestring.IdentifierNameStringLookupResult;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.Sets;
 import java.util.ArrayList;
 import java.util.List;
diff --git a/src/main/java/com/android/tools/r8/naming/InternalMapConsumerImpl.java b/src/main/java/com/android/tools/r8/naming/InternalMapConsumerImpl.java
index 95a6d57..64a162a 100644
--- a/src/main/java/com/android/tools/r8/naming/InternalMapConsumerImpl.java
+++ b/src/main/java/com/android/tools/r8/naming/InternalMapConsumerImpl.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.DiagnosticsHandler;
 import com.android.tools.r8.MapConsumer;
 import com.android.tools.r8.utils.internal.ChainableStringConsumer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 
 /***
  * Default implementation of an {@link InternalMapConsumer} that wraps around a {@link
diff --git a/src/main/java/com/android/tools/r8/naming/KotlinModuleSynthesizer.java b/src/main/java/com/android/tools/r8/naming/KotlinModuleSynthesizer.java
index 2ebd1f7..f95cf93 100644
--- a/src/main/java/com/android/tools/r8/naming/KotlinModuleSynthesizer.java
+++ b/src/main/java/com/android/tools/r8/naming/KotlinModuleSynthesizer.java
@@ -16,7 +16,7 @@
 import com.android.tools.r8.kotlin.KotlinMultiFileClassPartInfo;
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.utils.internal.Box;
-import com.android.tools.r8.utils.FileUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.android.tools.r8.utils.internal.collections.Pair;
 import com.google.common.collect.ImmutableList;
 import java.util.ArrayList;
diff --git a/src/main/java/com/android/tools/r8/naming/MemberNaming.java b/src/main/java/com/android/tools/r8/naming/MemberNaming.java
index b1a5319..1349438 100644
--- a/src/main/java/com/android/tools/r8/naming/MemberNaming.java
+++ b/src/main/java/com/android/tools/r8/naming/MemberNaming.java
@@ -20,9 +20,9 @@
 import com.android.tools.r8.references.TypeReference;
 import com.android.tools.r8.utils.CollectionUtils;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.internal.ArrayUtils;
 import com.android.tools.r8.utils.internal.ConsumerUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import com.google.common.collect.Iterables;
 import java.io.IOException;
diff --git a/src/main/java/com/android/tools/r8/naming/Minifier.java b/src/main/java/com/android/tools/r8/naming/Minifier.java
index 2fb8a1a..32acb0e 100644
--- a/src/main/java/com/android/tools/r8/naming/Minifier.java
+++ b/src/main/java/com/android/tools/r8/naming/Minifier.java
@@ -4,8 +4,8 @@
 package com.android.tools.r8.naming;
 
 import static com.android.tools.r8.graph.DexProgramClass.asProgramClassOrNull;
-import static com.android.tools.r8.utils.StringUtils.EMPTY_CHAR_ARRAY;
 import static com.android.tools.r8.utils.SymbolGenerationUtils.RESERVED_NAMES;
+import static com.android.tools.r8.utils.internal.StringUtils.EMPTY_CHAR_ARRAY;
 
 import com.android.tools.r8.errors.CompilationError;
 import com.android.tools.r8.graph.AppInfoWithClassHierarchy;
@@ -32,9 +32,9 @@
 import com.android.tools.r8.naming.FieldNameMinifier.FieldRenaming;
 import com.android.tools.r8.naming.MethodNameMinifier.MethodRenaming;
 import com.android.tools.r8.shaking.AppInfoWithLiveness;
-import com.android.tools.r8.utils.internal.ConsumerUtils;
 import com.android.tools.r8.utils.SymbolGenerationUtils;
 import com.android.tools.r8.utils.SymbolGenerationUtils.MixedCasing;
+import com.android.tools.r8.utils.internal.ConsumerUtils;
 import com.android.tools.r8.utils.timing.Timing;
 import java.util.ArrayList;
 import java.util.HashSet;
diff --git a/src/main/java/com/android/tools/r8/naming/ProguardMapReader.java b/src/main/java/com/android/tools/r8/naming/ProguardMapReader.java
index b66e72a..1d42a9f 100644
--- a/src/main/java/com/android/tools/r8/naming/ProguardMapReader.java
+++ b/src/main/java/com/android/tools/r8/naming/ProguardMapReader.java
@@ -20,10 +20,10 @@
 import com.android.tools.r8.position.Position;
 import com.android.tools.r8.utils.DescriptorUtils;
 import com.android.tools.r8.utils.IdentifierUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.internal.ArrayUtils;
 import com.android.tools.r8.utils.internal.BooleanBox;
 import com.android.tools.r8.utils.internal.Box;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.gson.JsonObject;
 import com.google.gson.JsonParser;
 import java.io.IOException;
diff --git a/src/main/java/com/android/tools/r8/naming/dexitembasedstring/RecordFieldNamesComputationInfo.java b/src/main/java/com/android/tools/r8/naming/dexitembasedstring/RecordFieldNamesComputationInfo.java
index a2f42c5..09a18fe 100644
--- a/src/main/java/com/android/tools/r8/naming/dexitembasedstring/RecordFieldNamesComputationInfo.java
+++ b/src/main/java/com/android/tools/r8/naming/dexitembasedstring/RecordFieldNamesComputationInfo.java
@@ -14,8 +14,8 @@
 import com.android.tools.r8.graph.lens.GraphLens;
 import com.android.tools.r8.naming.NamingLens;
 import com.android.tools.r8.utils.ComparatorUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.internal.ArrayUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.structural.CompareToVisitor;
 import com.android.tools.r8.utils.structural.HashingVisitor;
 import com.android.tools.r8.utils.structural.StructuralAcceptor;
diff --git a/src/main/java/com/android/tools/r8/naming/mappinginformation/ResidualSignatureMappingInformation.java b/src/main/java/com/android/tools/r8/naming/mappinginformation/ResidualSignatureMappingInformation.java
index 06df22a..945f433 100644
--- a/src/main/java/com/android/tools/r8/naming/mappinginformation/ResidualSignatureMappingInformation.java
+++ b/src/main/java/com/android/tools/r8/naming/mappinginformation/ResidualSignatureMappingInformation.java
@@ -11,9 +11,9 @@
 import com.android.tools.r8.naming.MapVersion;
 import com.android.tools.r8.naming.mappinginformation.MappingInformation.ReferentialMappingInformation;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
-import com.android.tools.r8.utils.StringUtils.BraceType;
 import com.android.tools.r8.utils.internal.ArrayUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils.BraceType;
 import com.google.gson.JsonElement;
 import com.google.gson.JsonObject;
 import com.google.gson.JsonPrimitive;
diff --git a/src/main/java/com/android/tools/r8/optimize/argumentpropagation/propagation/InFlowPropagatorDebugUtils.java b/src/main/java/com/android/tools/r8/optimize/argumentpropagation/propagation/InFlowPropagatorDebugUtils.java
index 8a237c0..f3ab669 100644
--- a/src/main/java/com/android/tools/r8/optimize/argumentpropagation/propagation/InFlowPropagatorDebugUtils.java
+++ b/src/main/java/com/android/tools/r8/optimize/argumentpropagation/propagation/InFlowPropagatorDebugUtils.java
@@ -9,9 +9,9 @@
 import com.android.tools.r8.optimize.argumentpropagation.codescanner.ConcreteValueState;
 import com.android.tools.r8.optimize.argumentpropagation.codescanner.FlowGraphStateProvider;
 import com.android.tools.r8.optimize.argumentpropagation.codescanner.ValueState;
-import com.android.tools.r8.utils.StringUtils;
-import com.android.tools.r8.utils.internal.TraversalContinuation;
 import com.android.tools.r8.utils.collections.WorkList;
+import com.android.tools.r8.utils.internal.StringUtils;
+import com.android.tools.r8.utils.internal.TraversalContinuation;
 import java.util.ArrayList;
 import java.util.List;
 
diff --git a/src/main/java/com/android/tools/r8/processkeeprules/FilteredKeepRulesBuilder.java b/src/main/java/com/android/tools/r8/processkeeprules/FilteredKeepRulesBuilder.java
index 86a4da5..a73ef11 100644
--- a/src/main/java/com/android/tools/r8/processkeeprules/FilteredKeepRulesBuilder.java
+++ b/src/main/java/com/android/tools/r8/processkeeprules/FilteredKeepRulesBuilder.java
@@ -19,7 +19,7 @@
 import com.android.tools.r8.shaking.WhyAreYouNotObfuscatingRule;
 import com.android.tools.r8.utils.InternalOptions.PackageObfuscationMode;
 import com.android.tools.r8.utils.Reporter;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.List;
 
diff --git a/src/main/java/com/android/tools/r8/profile/art/ArtProfileCompletenessChecker.java b/src/main/java/com/android/tools/r8/profile/art/ArtProfileCompletenessChecker.java
index c637cf3..17df3e8 100644
--- a/src/main/java/com/android/tools/r8/profile/art/ArtProfileCompletenessChecker.java
+++ b/src/main/java/com/android/tools/r8/profile/art/ArtProfileCompletenessChecker.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.graph.ProgramDefinition;
 import com.android.tools.r8.graph.ProgramMethod;
 import com.android.tools.r8.synthesis.SyntheticItems;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.Sets;
 import java.util.ArrayList;
 import java.util.List;
diff --git a/src/main/java/com/android/tools/r8/references/MethodReference.java b/src/main/java/com/android/tools/r8/references/MethodReference.java
index fd26b5d..afe4aa2 100644
--- a/src/main/java/com/android/tools/r8/references/MethodReference.java
+++ b/src/main/java/com/android/tools/r8/references/MethodReference.java
@@ -5,8 +5,8 @@
 
 import com.android.tools.r8.keepanno.annotations.KeepForApi;
 import com.android.tools.r8.utils.internal.ObjectUtils;
-import com.android.tools.r8.utils.StringUtils;
-import com.android.tools.r8.utils.StringUtils.BraceType;
+import com.android.tools.r8.utils.internal.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils.BraceType;
 import java.util.List;
 import java.util.Objects;
 
diff --git a/src/main/java/com/android/tools/r8/relocator/RelocatorCommand.java b/src/main/java/com/android/tools/r8/relocator/RelocatorCommand.java
index f52e2c3..6ffb7b9 100644
--- a/src/main/java/com/android/tools/r8/relocator/RelocatorCommand.java
+++ b/src/main/java/com/android/tools/r8/relocator/RelocatorCommand.java
@@ -27,16 +27,16 @@
 import com.android.tools.r8.shaking.ProguardPathList;
 import com.android.tools.r8.utils.AbortException;
 import com.android.tools.r8.utils.AndroidApp;
-import com.android.tools.r8.utils.internal.Box;
 import com.android.tools.r8.utils.DirectoryProgramResourceProvider;
 import com.android.tools.r8.utils.ExceptionDiagnostic;
 import com.android.tools.r8.utils.ExceptionUtils;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.FlagFile;
 import com.android.tools.r8.utils.InternalOptions;
 import com.android.tools.r8.utils.Reporter;
 import com.android.tools.r8.utils.StringDiagnostic;
 import com.android.tools.r8.utils.ThreadUtils;
+import com.android.tools.r8.utils.internal.Box;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.ImmutableSet;
@@ -229,7 +229,8 @@
         this.consumer = null;
         return this;
       }
-      FileUtils.validateOutputFile(outputPath, reporter);
+      FileUtils.validateOutputFile(
+          outputPath, errorMessage -> reporter.error(new StringDiagnostic(errorMessage)));
       this.consumer = createClassFileProgramOutputConsumer(outputPath, true);
       return this;
     }
diff --git a/src/main/java/com/android/tools/r8/relocator/RelocatorCommandLine.java b/src/main/java/com/android/tools/r8/relocator/RelocatorCommandLine.java
index f065d5e..7695824 100644
--- a/src/main/java/com/android/tools/r8/relocator/RelocatorCommandLine.java
+++ b/src/main/java/com/android/tools/r8/relocator/RelocatorCommandLine.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.Version;
 import com.android.tools.r8.origin.CommandLineOrigin;
 import com.android.tools.r8.utils.ExceptionUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 
 public class RelocatorCommandLine {
 
diff --git a/src/main/java/com/android/tools/r8/retrace/Partition.java b/src/main/java/com/android/tools/r8/retrace/Partition.java
index 502471f..34a7805 100644
--- a/src/main/java/com/android/tools/r8/retrace/Partition.java
+++ b/src/main/java/com/android/tools/r8/retrace/Partition.java
@@ -15,7 +15,7 @@
 import com.android.tools.r8.retrace.internal.MappingPartitionMetadataInternal;
 import com.android.tools.r8.utils.ExceptionUtils;
 import com.android.tools.r8.utils.Reporter;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.util.LinkedHashMap;
 import java.util.Map;
diff --git a/src/main/java/com/android/tools/r8/retrace/PartitionCommandParser.java b/src/main/java/com/android/tools/r8/retrace/PartitionCommandParser.java
index 59572f3..cac6075 100644
--- a/src/main/java/com/android/tools/r8/retrace/PartitionCommandParser.java
+++ b/src/main/java/com/android/tools/r8/retrace/PartitionCommandParser.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.utils.OptionsParsing.ParseContext;
 import com.android.tools.r8.utils.PartitionMapZipContainer;
 import com.android.tools.r8.utils.StringDiagnostic;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Paths;
 import java.util.List;
diff --git a/src/main/java/com/android/tools/r8/retrace/Retrace.java b/src/main/java/com/android/tools/r8/retrace/Retrace.java
index 465e303..7945634 100644
--- a/src/main/java/com/android/tools/r8/retrace/Retrace.java
+++ b/src/main/java/com/android/tools/r8/retrace/Retrace.java
@@ -23,7 +23,7 @@
 import com.android.tools.r8.utils.OptionsParsing.ParseContext;
 import com.android.tools.r8.utils.PartitionMapZipContainer;
 import com.android.tools.r8.utils.StringDiagnostic;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.timing.Timing;
 import com.google.common.base.Charsets;
 import com.google.common.collect.ImmutableList;
diff --git a/src/main/java/com/android/tools/r8/retrace/StringRetrace.java b/src/main/java/com/android/tools/r8/retrace/StringRetrace.java
index 2229315..42ffe63 100644
--- a/src/main/java/com/android/tools/r8/retrace/StringRetrace.java
+++ b/src/main/java/com/android/tools/r8/retrace/StringRetrace.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.keepanno.annotations.KeepForApi;
 import com.android.tools.r8.retrace.internal.RetraceStackFrameResultWithContextImpl;
 import com.android.tools.r8.retrace.internal.StackTraceElementStringProxy;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.HashSet;
diff --git a/src/main/java/com/android/tools/r8/retrace/internal/MetadataAdditionalInfo.java b/src/main/java/com/android/tools/r8/retrace/internal/MetadataAdditionalInfo.java
index b0bb567..c4b3bab 100644
--- a/src/main/java/com/android/tools/r8/retrace/internal/MetadataAdditionalInfo.java
+++ b/src/main/java/com/android/tools/r8/retrace/internal/MetadataAdditionalInfo.java
@@ -6,8 +6,8 @@
 
 import com.android.tools.r8.dex.CompatByteBuffer;
 import com.android.tools.r8.retrace.RetracePartitionException;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.internal.SerializationUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import com.google.common.hash.Hashing;
 import java.io.ByteArrayOutputStream;
diff --git a/src/main/java/com/android/tools/r8/retrace/internal/MetadataPartitionCollection.java b/src/main/java/com/android/tools/r8/retrace/internal/MetadataPartitionCollection.java
index 7a58c72..e8930d7 100644
--- a/src/main/java/com/android/tools/r8/retrace/internal/MetadataPartitionCollection.java
+++ b/src/main/java/com/android/tools/r8/retrace/internal/MetadataPartitionCollection.java
@@ -5,8 +5,8 @@
 package com.android.tools.r8.retrace.internal;
 
 import com.android.tools.r8.dex.CompatByteBuffer;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.internal.SerializationUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.DataOutputStream;
 import java.io.IOException;
 import java.nio.charset.StandardCharsets;
diff --git a/src/main/java/com/android/tools/r8/retrace/internal/ProguardMapPartitionerOnClassNameToText.java b/src/main/java/com/android/tools/r8/retrace/internal/ProguardMapPartitionerOnClassNameToText.java
index e398f1b..264f6de 100644
--- a/src/main/java/com/android/tools/r8/retrace/internal/ProguardMapPartitionerOnClassNameToText.java
+++ b/src/main/java/com/android/tools/r8/retrace/internal/ProguardMapPartitionerOnClassNameToText.java
@@ -25,7 +25,7 @@
 import com.android.tools.r8.retrace.internal.ProguardMapReaderWithFiltering.ProguardMapReaderWithFilteringMappedBuffer;
 import com.android.tools.r8.utils.ExceptionDiagnostic;
 import com.android.tools.r8.utils.StringDiagnostic;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.TriConsumer;
 import java.io.IOException;
 import java.nio.charset.StandardCharsets;
diff --git a/src/main/java/com/android/tools/r8/retrace/internal/StackTraceElementStringProxy.java b/src/main/java/com/android/tools/r8/retrace/internal/StackTraceElementStringProxy.java
index 3294ca1..327eb17 100644
--- a/src/main/java/com/android/tools/r8/retrace/internal/StackTraceElementStringProxy.java
+++ b/src/main/java/com/android/tools/r8/retrace/internal/StackTraceElementStringProxy.java
@@ -15,7 +15,7 @@
 import com.android.tools.r8.retrace.RetracedFieldReference;
 import com.android.tools.r8.retrace.RetracedTypeReference;
 import com.android.tools.r8.retrace.StackTraceElementProxy;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.TriFunction;
 import java.util.ArrayList;
 import java.util.List;
diff --git a/src/main/java/com/android/tools/r8/shaking/ProguardClassSpecification.java b/src/main/java/com/android/tools/r8/shaking/ProguardClassSpecification.java
index 896787b..f013ca3 100644
--- a/src/main/java/com/android/tools/r8/shaking/ProguardClassSpecification.java
+++ b/src/main/java/com/android/tools/r8/shaking/ProguardClassSpecification.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.position.Position;
 import com.android.tools.r8.position.TextPosition;
 import com.android.tools.r8.position.TextRange;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.Collection;
 import java.util.Iterator;
diff --git a/src/main/java/com/android/tools/r8/shaking/ProguardConfiguration.java b/src/main/java/com/android/tools/r8/shaking/ProguardConfiguration.java
index c199630..04a007b 100644
--- a/src/main/java/com/android/tools/r8/shaking/ProguardConfiguration.java
+++ b/src/main/java/com/android/tools/r8/shaking/ProguardConfiguration.java
@@ -16,7 +16,7 @@
 import com.android.tools.r8.utils.InternalOptions.PackageObfuscationMode;
 import com.android.tools.r8.utils.Reporter;
 import com.android.tools.r8.utils.StringDiagnostic;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Iterables;
 import com.google.common.collect.Sets;
diff --git a/src/main/java/com/android/tools/r8/shaking/ProguardConfigurationParser.java b/src/main/java/com/android/tools/r8/shaking/ProguardConfigurationParser.java
index 5257cc2..0415c09 100644
--- a/src/main/java/com/android/tools/r8/shaking/ProguardConfigurationParser.java
+++ b/src/main/java/com/android/tools/r8/shaking/ProguardConfigurationParser.java
@@ -31,9 +31,9 @@
 import com.android.tools.r8.utils.InternalOptions.PackageObfuscationMode;
 import com.android.tools.r8.utils.Reporter;
 import com.android.tools.r8.utils.StringDiagnostic;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.internal.CharPredicate;
 import com.android.tools.r8.utils.internal.LongInterval;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.ThrowingAction;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
diff --git a/src/main/java/com/android/tools/r8/shaking/ProguardConfigurationRule.java b/src/main/java/com/android/tools/r8/shaking/ProguardConfigurationRule.java
index 8841a9e..c8a7c91 100644
--- a/src/main/java/com/android/tools/r8/shaking/ProguardConfigurationRule.java
+++ b/src/main/java/com/android/tools/r8/shaking/ProguardConfigurationRule.java
@@ -21,9 +21,9 @@
 import com.android.tools.r8.shaking.ProguardWildcard.BackReference;
 import com.android.tools.r8.shaking.rootset.RootSetBuilder;
 import com.android.tools.r8.shaking.rootset.RootSetBuilderAnnotationIndex;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.internal.IterableUtils;
 import com.android.tools.r8.utils.internal.OptionalBool;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.Iterables;
 import java.util.List;
 import java.util.Objects;
diff --git a/src/main/java/com/android/tools/r8/shaking/ProguardMemberRule.java b/src/main/java/com/android/tools/r8/shaking/ProguardMemberRule.java
index c3c5d01..a75dc5f 100644
--- a/src/main/java/com/android/tools/r8/shaking/ProguardMemberRule.java
+++ b/src/main/java/com/android/tools/r8/shaking/ProguardMemberRule.java
@@ -15,9 +15,9 @@
 import com.android.tools.r8.graph.DexType;
 import com.android.tools.r8.shaking.ProguardConfigurationParser.IdentifierPatternWithWildcardsAndNegation;
 import com.android.tools.r8.shaking.rootset.RootSetBuilder;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.internal.IterableUtils;
 import com.android.tools.r8.utils.internal.ObjectUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import com.google.common.collect.Iterables;
 import java.util.ArrayList;
diff --git a/src/main/java/com/android/tools/r8/shaking/ProguardTypeMatcher.java b/src/main/java/com/android/tools/r8/shaking/ProguardTypeMatcher.java
index 10d02c4..9305d52 100644
--- a/src/main/java/com/android/tools/r8/shaking/ProguardTypeMatcher.java
+++ b/src/main/java/com/android/tools/r8/shaking/ProguardTypeMatcher.java
@@ -13,9 +13,9 @@
 import com.android.tools.r8.shaking.ProguardWildcard.BackReference;
 import com.android.tools.r8.shaking.ProguardWildcard.Pattern;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
-import com.android.tools.r8.utils.StringUtils.BraceType;
 import com.android.tools.r8.utils.internal.IterableUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils.BraceType;
 import com.google.common.collect.ImmutableList;
 import it.unimi.dsi.fastutil.ints.Int2ReferenceMap;
 import it.unimi.dsi.fastutil.ints.Int2ReferenceOpenHashMap;
diff --git a/src/main/java/com/android/tools/r8/shaking/UnusedItemsPrinter.java b/src/main/java/com/android/tools/r8/shaking/UnusedItemsPrinter.java
index d0445d1..a09803e 100644
--- a/src/main/java/com/android/tools/r8/shaking/UnusedItemsPrinter.java
+++ b/src/main/java/com/android/tools/r8/shaking/UnusedItemsPrinter.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.graph.DexEncodedMethod;
 import com.android.tools.r8.graph.DexProgramClass;
 import com.android.tools.r8.graph.DexType;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.collections.Pair;
 import java.util.ArrayList;
 import java.util.List;
diff --git a/src/main/java/com/android/tools/r8/shaking/WhyAreYouKeepingConsumer.java b/src/main/java/com/android/tools/r8/shaking/WhyAreYouKeepingConsumer.java
index 6c587e1..f8f2042 100644
--- a/src/main/java/com/android/tools/r8/shaking/WhyAreYouKeepingConsumer.java
+++ b/src/main/java/com/android/tools/r8/shaking/WhyAreYouKeepingConsumer.java
@@ -21,8 +21,8 @@
 import com.android.tools.r8.references.TypeReference;
 import com.android.tools.r8.utils.DescriptorUtils;
 import com.android.tools.r8.utils.ListUtils;
-import com.android.tools.r8.utils.StringUtils;
-import com.android.tools.r8.utils.StringUtils.BraceType;
+import com.android.tools.r8.utils.internal.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils.BraceType;
 import com.android.tools.r8.utils.internal.collections.Pair;
 import java.io.PrintStream;
 import java.util.ArrayDeque;
diff --git a/src/main/java/com/android/tools/r8/shaking/assume/AssumeMethodInfoCollection.java b/src/main/java/com/android/tools/r8/shaking/assume/AssumeMethodInfoCollection.java
index 22b879c..6f55e0c 100644
--- a/src/main/java/com/android/tools/r8/shaking/assume/AssumeMethodInfoCollection.java
+++ b/src/main/java/com/android/tools/r8/shaking/assume/AssumeMethodInfoCollection.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.shaking.ProguardMemberRuleValue;
 import com.android.tools.r8.utils.MapUtils;
 import com.android.tools.r8.utils.internal.ObjectUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.List;
diff --git a/src/main/java/com/android/tools/r8/tracereferences/Formatter.java b/src/main/java/com/android/tools/r8/tracereferences/Formatter.java
index 701391d..b84274e 100644
--- a/src/main/java/com/android/tools/r8/tracereferences/Formatter.java
+++ b/src/main/java/com/android/tools/r8/tracereferences/Formatter.java
@@ -14,9 +14,9 @@
 import com.android.tools.r8.tracereferences.internal.TraceReferencesResult;
 import com.android.tools.r8.utils.ListUtils;
 import com.android.tools.r8.utils.MapUtils;
-import com.android.tools.r8.utils.StringUtils;
-import com.android.tools.r8.utils.StringUtils.BraceType;
 import com.android.tools.r8.utils.internal.IterableUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils.BraceType;
 import com.google.common.collect.Streams;
 import java.util.ArrayList;
 import java.util.Collections;
diff --git a/src/main/java/com/android/tools/r8/tracereferences/KeepRuleFormatter.java b/src/main/java/com/android/tools/r8/tracereferences/KeepRuleFormatter.java
index ea9be1b..e446104 100644
--- a/src/main/java/com/android/tools/r8/tracereferences/KeepRuleFormatter.java
+++ b/src/main/java/com/android/tools/r8/tracereferences/KeepRuleFormatter.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.tracereferences.TraceReferencesConsumer.TracedClass;
 import com.android.tools.r8.tracereferences.TraceReferencesConsumer.TracedField;
 import com.android.tools.r8.tracereferences.TraceReferencesConsumer.TracedMethod;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 
 class KeepRuleFormatter extends Formatter {
diff --git a/src/main/java/com/android/tools/r8/tracereferences/TraceReferences.java b/src/main/java/com/android/tools/r8/tracereferences/TraceReferences.java
index 4dda81e..2539bb5 100644
--- a/src/main/java/com/android/tools/r8/tracereferences/TraceReferences.java
+++ b/src/main/java/com/android/tools/r8/tracereferences/TraceReferences.java
@@ -25,8 +25,8 @@
 import com.android.tools.r8.utils.InternalOptions;
 import com.android.tools.r8.utils.ProgramResourceProviderUtils;
 import com.android.tools.r8.utils.ProgramResourceUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.ThreadUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.timing.Timing;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
diff --git a/src/main/java/com/android/tools/r8/tracereferences/TraceReferencesCommand.java b/src/main/java/com/android/tools/r8/tracereferences/TraceReferencesCommand.java
index 3e26a3f..7a89f0b 100644
--- a/src/main/java/com/android/tools/r8/tracereferences/TraceReferencesCommand.java
+++ b/src/main/java/com/android/tools/r8/tracereferences/TraceReferencesCommand.java
@@ -3,10 +3,10 @@
 // BSD-style license that can be found in the LICENSE file.
 package com.android.tools.r8.tracereferences;
 
-import static com.android.tools.r8.utils.FileUtils.isArchive;
-import static com.android.tools.r8.utils.FileUtils.isClassFile;
-import static com.android.tools.r8.utils.FileUtils.isDexFile;
 import static com.android.tools.r8.utils.InternalOptions.ASM_VERSION;
+import static com.android.tools.r8.utils.internal.FileUtils.isArchive;
+import static com.android.tools.r8.utils.internal.FileUtils.isClassFile;
+import static com.android.tools.r8.utils.internal.FileUtils.isDexFile;
 
 import com.android.tools.r8.ArchiveClassFileProvider;
 import com.android.tools.r8.ClassConflictResolver;
@@ -24,7 +24,6 @@
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.origin.PathOrigin;
 import com.android.tools.r8.utils.ArchiveResourceProvider;
-import com.android.tools.r8.utils.internal.Box;
 import com.android.tools.r8.utils.ExceptionDiagnostic;
 import com.android.tools.r8.utils.ExceptionUtils;
 import com.android.tools.r8.utils.InternalOptions;
@@ -32,6 +31,7 @@
 import com.android.tools.r8.utils.ProgramResourceProviderUtils;
 import com.android.tools.r8.utils.Reporter;
 import com.android.tools.r8.utils.StringDiagnostic;
+import com.android.tools.r8.utils.internal.Box;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 import java.io.IOException;
diff --git a/src/main/java/com/android/tools/r8/tracereferences/TraceReferencesCommandParser.java b/src/main/java/com/android/tools/r8/tracereferences/TraceReferencesCommandParser.java
index dfaac56..8f46a82 100644
--- a/src/main/java/com/android/tools/r8/tracereferences/TraceReferencesCommandParser.java
+++ b/src/main/java/com/android/tools/r8/tracereferences/TraceReferencesCommandParser.java
@@ -22,8 +22,8 @@
 import com.android.tools.r8.utils.ExceptionDiagnostic;
 import com.android.tools.r8.utils.FlagFile;
 import com.android.tools.r8.utils.StringDiagnostic;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.ZipUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
diff --git a/src/main/java/com/android/tools/r8/utils/AarArchiveResourceProvider.java b/src/main/java/com/android/tools/r8/utils/AarArchiveResourceProvider.java
index 5072fda..68e6c1f 100644
--- a/src/main/java/com/android/tools/r8/utils/AarArchiveResourceProvider.java
+++ b/src/main/java/com/android/tools/r8/utils/AarArchiveResourceProvider.java
@@ -3,7 +3,7 @@
 // BSD-style license that can be found in the LICENSE file.
 package com.android.tools.r8.utils;
 
-import static com.android.tools.r8.utils.FileUtils.isArchive;
+import static com.android.tools.r8.utils.internal.FileUtils.isArchive;
 
 import com.android.tools.r8.DataResourceProvider;
 import com.android.tools.r8.ProgramResource;
@@ -14,6 +14,7 @@
 import com.android.tools.r8.origin.ArchiveEntryOrigin;
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.origin.PathOrigin;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.io.ByteStreams;
 import java.io.IOException;
 import java.io.InputStream;
diff --git a/src/main/java/com/android/tools/r8/utils/AndroidApiLevelUtils.java b/src/main/java/com/android/tools/r8/utils/AndroidApiLevelUtils.java
index 77f1485..ee18ed9 100644
--- a/src/main/java/com/android/tools/r8/utils/AndroidApiLevelUtils.java
+++ b/src/main/java/com/android/tools/r8/utils/AndroidApiLevelUtils.java
@@ -27,9 +27,10 @@
 import com.android.tools.r8.ir.analysis.value.SingleValue;
 import com.android.tools.r8.ir.optimize.inliner.NopWhyAreYouNotInliningReporter;
 import com.android.tools.r8.ir.optimize.inliner.WhyAreYouNotInliningReporter;
+import com.android.tools.r8.utils.collections.WorkList;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.TraversalContinuation;
 import com.android.tools.r8.utils.internal.collections.Pair;
-import com.android.tools.r8.utils.collections.WorkList;
 import com.google.common.collect.Sets;
 import java.util.Collections;
 import java.util.Set;
diff --git a/src/main/java/com/android/tools/r8/utils/AndroidApp.java b/src/main/java/com/android/tools/r8/utils/AndroidApp.java
index c916f86..24d6189 100644
--- a/src/main/java/com/android/tools/r8/utils/AndroidApp.java
+++ b/src/main/java/com/android/tools/r8/utils/AndroidApp.java
@@ -3,14 +3,14 @@
 // BSD-style license that can be found in the LICENSE file.
 package com.android.tools.r8.utils;
 
-import static com.android.tools.r8.utils.internal.ConsumerUtils.emptyConsumer;
-import static com.android.tools.r8.utils.FileUtils.CLASS_EXTENSION;
-import static com.android.tools.r8.utils.FileUtils.isAarFile;
-import static com.android.tools.r8.utils.FileUtils.isArchive;
-import static com.android.tools.r8.utils.FileUtils.isClassFile;
-import static com.android.tools.r8.utils.FileUtils.isDexFile;
 import static com.android.tools.r8.utils.InternalOptions.ASM_VERSION;
 import static com.android.tools.r8.utils.ZipUtils.writeToZipStream;
+import static com.android.tools.r8.utils.internal.ConsumerUtils.emptyConsumer;
+import static com.android.tools.r8.utils.internal.FileUtils.CLASS_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.isAarFile;
+import static com.android.tools.r8.utils.internal.FileUtils.isArchive;
+import static com.android.tools.r8.utils.internal.FileUtils.isClassFile;
+import static com.android.tools.r8.utils.internal.FileUtils.isDexFile;
 import static java.nio.charset.StandardCharsets.UTF_8;
 
 import com.android.tools.r8.AndroidResourceInput;
@@ -52,6 +52,7 @@
 import com.android.tools.r8.synthesis.SyntheticItems;
 import com.android.tools.r8.utils.internal.IntBox;
 import com.android.tools.r8.utils.internal.StreamUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.collections.Pair;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import com.android.tools.r8.utils.timing.Timing;
diff --git a/src/main/java/com/android/tools/r8/utils/ArchiveResourceProvider.java b/src/main/java/com/android/tools/r8/utils/ArchiveResourceProvider.java
index da23e02..20bbef6 100644
--- a/src/main/java/com/android/tools/r8/utils/ArchiveResourceProvider.java
+++ b/src/main/java/com/android/tools/r8/utils/ArchiveResourceProvider.java
@@ -3,7 +3,7 @@
 // BSD-style license that can be found in the LICENSE file.
 package com.android.tools.r8.utils;
 
-import static com.android.tools.r8.utils.FileUtils.isArchive;
+import static com.android.tools.r8.utils.internal.FileUtils.isArchive;
 import static com.google.common.base.Predicates.alwaysTrue;
 
 import com.android.tools.r8.DataResourceProvider;
@@ -17,6 +17,7 @@
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.origin.PathOrigin;
 import com.android.tools.r8.shaking.FilteredClassPath;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.io.ByteStreams;
 import java.io.IOException;
 import java.io.InputStream;
diff --git a/src/main/java/com/android/tools/r8/utils/ArchiveResourceProviderUtils.java b/src/main/java/com/android/tools/r8/utils/ArchiveResourceProviderUtils.java
index 49582b8..e9967a4 100644
--- a/src/main/java/com/android/tools/r8/utils/ArchiveResourceProviderUtils.java
+++ b/src/main/java/com/android/tools/r8/utils/ArchiveResourceProviderUtils.java
@@ -14,6 +14,7 @@
 import com.android.tools.r8.origin.ArchiveEntryOrigin;
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.utils.internal.BooleanBox;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.io.ByteStreams;
 import java.io.IOException;
 import java.io.InputStream;
diff --git a/src/main/java/com/android/tools/r8/utils/ByteDataUtils.java b/src/main/java/com/android/tools/r8/utils/ByteDataUtils.java
new file mode 100644
index 0000000..e3c8171
--- /dev/null
+++ b/src/main/java/com/android/tools/r8/utils/ByteDataUtils.java
@@ -0,0 +1,20 @@
+// Copyright (c) 2026, the R8 project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+package com.android.tools.r8.utils;
+
+import com.android.tools.r8.ByteDataView;
+import com.android.tools.r8.utils.internal.FileUtils;
+import java.io.IOException;
+import java.io.OutputStream;
+import java.nio.file.Path;
+
+public class ByteDataUtils {
+
+  public static void writeToFile(Path output, OutputStream defValue, ByteDataView contents)
+      throws IOException {
+    FileUtils.writeToFile(
+        output, defValue, contents.getBuffer(), contents.getOffset(), contents.getLength());
+  }
+}
diff --git a/src/main/java/com/android/tools/r8/utils/CfLineToMethodMapper.java b/src/main/java/com/android/tools/r8/utils/CfLineToMethodMapper.java
index 008491f..7a25330 100644
--- a/src/main/java/com/android/tools/r8/utils/CfLineToMethodMapper.java
+++ b/src/main/java/com/android/tools/r8/utils/CfLineToMethodMapper.java
@@ -3,7 +3,7 @@
 // BSD-style license that can be found in the LICENSE file.
 package com.android.tools.r8.utils;
 
-import static com.android.tools.r8.utils.FileUtils.CLASS_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.CLASS_EXTENSION;
 
 import com.android.tools.r8.ProgramResource;
 import com.android.tools.r8.ProgramResource.Kind;
diff --git a/src/main/java/com/android/tools/r8/utils/DescriptorUtils.java b/src/main/java/com/android/tools/r8/utils/DescriptorUtils.java
index b035cb8..ac0b7a2 100644
--- a/src/main/java/com/android/tools/r8/utils/DescriptorUtils.java
+++ b/src/main/java/com/android/tools/r8/utils/DescriptorUtils.java
@@ -4,8 +4,8 @@
 
 package com.android.tools.r8.utils;
 
-import static com.android.tools.r8.utils.FileUtils.CLASS_EXTENSION;
-import static com.android.tools.r8.utils.FileUtils.MODULES_PREFIX;
+import static com.android.tools.r8.utils.internal.FileUtils.CLASS_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.MODULES_PREFIX;
 
 import com.android.tools.r8.dex.Constants;
 import com.android.tools.r8.errors.CompilationError;
@@ -13,6 +13,7 @@
 import com.android.tools.r8.graph.DexString;
 import com.android.tools.r8.graph.DexType;
 import com.android.tools.r8.naming.ClassNameMapper;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import com.google.common.collect.ImmutableMap;
 import java.io.File;
diff --git a/src/main/java/com/android/tools/r8/utils/DeterminismChecker.java b/src/main/java/com/android/tools/r8/utils/DeterminismChecker.java
index 3d53998..00f2f7f 100644
--- a/src/main/java/com/android/tools/r8/utils/DeterminismChecker.java
+++ b/src/main/java/com/android/tools/r8/utils/DeterminismChecker.java
@@ -7,6 +7,7 @@
 import com.android.tools.r8.graph.DexEncodedMethod;
 import com.android.tools.r8.graph.DexProgramClass;
 import com.android.tools.r8.graph.ProgramClass;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.ThrowingConsumer;
 import java.io.BufferedReader;
 import java.io.BufferedWriter;
diff --git a/src/main/java/com/android/tools/r8/utils/DexFilePerClassFileConsumerUtils.java b/src/main/java/com/android/tools/r8/utils/DexFilePerClassFileConsumerUtils.java
index fc1882b..0af709e 100644
--- a/src/main/java/com/android/tools/r8/utils/DexFilePerClassFileConsumerUtils.java
+++ b/src/main/java/com/android/tools/r8/utils/DexFilePerClassFileConsumerUtils.java
@@ -3,11 +3,12 @@
 // BSD-style license that can be found in the LICENSE file.
 package com.android.tools.r8.utils;
 
-import static com.android.tools.r8.utils.FileUtils.DEX_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.DEX_EXTENSION;
 
 import com.android.tools.r8.ProgramResource;
 import com.android.tools.r8.Resource;
 import com.android.tools.r8.ResourceException;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.io.ByteStreams;
 import com.google.common.io.Closer;
 import java.io.BufferedOutputStream;
diff --git a/src/main/java/com/android/tools/r8/utils/DexIndexedConsumerUtils.java b/src/main/java/com/android/tools/r8/utils/DexIndexedConsumerUtils.java
index 96cd99b..72b13a2 100644
--- a/src/main/java/com/android/tools/r8/utils/DexIndexedConsumerUtils.java
+++ b/src/main/java/com/android/tools/r8/utils/DexIndexedConsumerUtils.java
@@ -7,6 +7,7 @@
 import com.android.tools.r8.DataEntryResource;
 import com.android.tools.r8.ProgramResource;
 import com.android.tools.r8.ResourceException;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.io.ByteStreams;
 import com.google.common.io.Closer;
 import java.io.BufferedOutputStream;
diff --git a/src/main/java/com/android/tools/r8/utils/DexUtils.java b/src/main/java/com/android/tools/r8/utils/DexUtils.java
index 265a130..9b8b3bd 100644
--- a/src/main/java/com/android/tools/r8/utils/DexUtils.java
+++ b/src/main/java/com/android/tools/r8/utils/DexUtils.java
@@ -4,6 +4,8 @@
 
 package com.android.tools.r8.utils;
 
+import com.android.tools.r8.utils.internal.FileUtils;
+
 public class DexUtils {
   public static String getDefaultDexFileName(int fileIndex) {
     return fileIndex == 0
diff --git a/src/main/java/com/android/tools/r8/utils/DirectoryBuilder.java b/src/main/java/com/android/tools/r8/utils/DirectoryBuilder.java
index f78983f..4a5f55c 100644
--- a/src/main/java/com/android/tools/r8/utils/DirectoryBuilder.java
+++ b/src/main/java/com/android/tools/r8/utils/DirectoryBuilder.java
@@ -61,7 +61,7 @@
     Path target = root.resolve(name.replace(NAME_SEPARATOR, File.separatorChar));
     try {
       Files.createDirectories(target.getParent());
-      FileUtils.writeToFile(target, null, content);
+      ByteDataUtils.writeToFile(target, null, content);
     } catch (IOException e) {
       handler.error(new ExceptionDiagnostic(e, new PathOrigin(target)));
     }
diff --git a/src/main/java/com/android/tools/r8/utils/DirectoryProgramResourceProvider.java b/src/main/java/com/android/tools/r8/utils/DirectoryProgramResourceProvider.java
index 07431a0..b75a00e 100644
--- a/src/main/java/com/android/tools/r8/utils/DirectoryProgramResourceProvider.java
+++ b/src/main/java/com/android/tools/r8/utils/DirectoryProgramResourceProvider.java
@@ -3,7 +3,7 @@
 // BSD-style license that can be found in the LICENSE file.
 package com.android.tools.r8.utils;
 
-import static com.android.tools.r8.utils.FileUtils.isClassFile;
+import static com.android.tools.r8.utils.internal.FileUtils.isClassFile;
 
 import com.android.tools.r8.DataEntryResource;
 import com.android.tools.r8.DataResourceProvider;
diff --git a/src/main/java/com/android/tools/r8/utils/EmbeddedRulesExtractor.java b/src/main/java/com/android/tools/r8/utils/EmbeddedRulesExtractor.java
index 5332793..8bca1e5 100644
--- a/src/main/java/com/android/tools/r8/utils/EmbeddedRulesExtractor.java
+++ b/src/main/java/com/android/tools/r8/utils/EmbeddedRulesExtractor.java
@@ -12,6 +12,7 @@
 import com.android.tools.r8.shaking.ProguardConfigurationSource;
 import com.android.tools.r8.shaking.ProguardConfigurationSourceBytes;
 import com.android.tools.r8.utils.internal.SemanticVersion;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.Iterables;
 import java.io.InputStream;
 import java.util.ArrayList;
diff --git a/src/main/java/com/android/tools/r8/utils/FlagFile.java b/src/main/java/com/android/tools/r8/utils/FlagFile.java
index df999e0..4bb536b 100644
--- a/src/main/java/com/android/tools/r8/utils/FlagFile.java
+++ b/src/main/java/com/android/tools/r8/utils/FlagFile.java
@@ -6,6 +6,7 @@
 
 import com.android.tools.r8.Diagnostic;
 import com.android.tools.r8.origin.Origin;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.Path;
diff --git a/src/main/java/com/android/tools/r8/utils/InternalArchiveClassFileProvider.java b/src/main/java/com/android/tools/r8/utils/InternalArchiveClassFileProvider.java
index 7955dc0..4356a9e 100644
--- a/src/main/java/com/android/tools/r8/utils/InternalArchiveClassFileProvider.java
+++ b/src/main/java/com/android/tools/r8/utils/InternalArchiveClassFileProvider.java
@@ -3,8 +3,8 @@
 // BSD-style license that can be found in the LICENSE file.
 package com.android.tools.r8.utils;
 
-import static com.android.tools.r8.utils.FileUtils.CLASS_EXTENSION;
-import static com.android.tools.r8.utils.FileUtils.isArchive;
+import static com.android.tools.r8.utils.internal.FileUtils.CLASS_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.isArchive;
 
 import com.android.tools.r8.ClassFileResourceProvider;
 import com.android.tools.r8.DataDirectoryResource;
@@ -18,6 +18,7 @@
 import com.android.tools.r8.origin.ArchiveEntryOrigin;
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.origin.PathOrigin;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.io.ByteStreams;
 import java.io.IOException;
 import java.io.InputStream;
diff --git a/src/main/java/com/android/tools/r8/utils/InternalGlobalSyntheticsProgramConsumer.java b/src/main/java/com/android/tools/r8/utils/InternalGlobalSyntheticsProgramConsumer.java
index bfbfa4a..bc3fd4b 100644
--- a/src/main/java/com/android/tools/r8/utils/InternalGlobalSyntheticsProgramConsumer.java
+++ b/src/main/java/com/android/tools/r8/utils/InternalGlobalSyntheticsProgramConsumer.java
@@ -3,7 +3,7 @@
 // BSD-style license that can be found in the LICENSE file.
 package com.android.tools.r8.utils;
 
-import static com.android.tools.r8.utils.FileUtils.GLOBAL_SYNTHETIC_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.GLOBAL_SYNTHETIC_EXTENSION;
 
 import com.android.tools.r8.ByteBufferProvider;
 import com.android.tools.r8.ByteDataView;
diff --git a/src/main/java/com/android/tools/r8/utils/InternalGlobalSyntheticsProgramProvider.java b/src/main/java/com/android/tools/r8/utils/InternalGlobalSyntheticsProgramProvider.java
index 4ec6972..626868e 100644
--- a/src/main/java/com/android/tools/r8/utils/InternalGlobalSyntheticsProgramProvider.java
+++ b/src/main/java/com/android/tools/r8/utils/InternalGlobalSyntheticsProgramProvider.java
@@ -12,6 +12,7 @@
 import com.android.tools.r8.ResourceException;
 import com.android.tools.r8.Version;
 import com.android.tools.r8.origin.Origin;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.io.ByteStreams;
 import java.io.IOException;
 import java.nio.charset.StandardCharsets;
diff --git a/src/main/java/com/android/tools/r8/utils/InternalOptions.java b/src/main/java/com/android/tools/r8/utils/InternalOptions.java
index b443691..c5e9005 100644
--- a/src/main/java/com/android/tools/r8/utils/InternalOptions.java
+++ b/src/main/java/com/android/tools/r8/utils/InternalOptions.java
@@ -116,6 +116,7 @@
 import com.android.tools.r8.utils.internal.AssertionUtils;
 import com.android.tools.r8.utils.internal.ConsumerUtils;
 import com.android.tools.r8.utils.internal.QuadConsumer;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.ThrowingConsumer;
 import com.android.tools.r8.utils.internal.TriConsumer;
 import com.android.tools.r8.utils.internal.TriFunction;
diff --git a/src/main/java/com/android/tools/r8/utils/MainDexListParser.java b/src/main/java/com/android/tools/r8/utils/MainDexListParser.java
index 136ae2a..ac0d145 100644
--- a/src/main/java/com/android/tools/r8/utils/MainDexListParser.java
+++ b/src/main/java/com/android/tools/r8/utils/MainDexListParser.java
@@ -4,7 +4,7 @@
 package com.android.tools.r8.utils;
 
 import static com.android.tools.r8.utils.DescriptorUtils.JAVA_PACKAGE_SEPARATOR;
-import static com.android.tools.r8.utils.FileUtils.CLASS_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.CLASS_EXTENSION;
 
 import com.android.tools.r8.ResourceException;
 import com.android.tools.r8.StringResource;
@@ -12,6 +12,7 @@
 import com.android.tools.r8.graph.DexItemFactory;
 import com.android.tools.r8.graph.DexType;
 import com.android.tools.r8.position.TextPosition;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.Sets;
 import java.util.Set;
 
diff --git a/src/main/java/com/android/tools/r8/utils/MapUtils.java b/src/main/java/com/android/tools/r8/utils/MapUtils.java
index c3ae681..3aacbd2 100644
--- a/src/main/java/com/android/tools/r8/utils/MapUtils.java
+++ b/src/main/java/com/android/tools/r8/utils/MapUtils.java
@@ -4,9 +4,10 @@
 
 package com.android.tools.r8.utils;
 
-import com.android.tools.r8.utils.StringUtils.BraceType;
 import com.android.tools.r8.utils.internal.AssertionUtils;
 import com.android.tools.r8.utils.internal.BiForEachable;
+import com.android.tools.r8.utils.internal.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils.BraceType;
 import com.android.tools.r8.utils.internal.ThrowingBiPredicate;
 import com.android.tools.r8.utils.internal.TriFunction;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
diff --git a/src/main/java/com/android/tools/r8/utils/RetracerForCodePrinting.java b/src/main/java/com/android/tools/r8/utils/RetracerForCodePrinting.java
index 1b772b7..2642510 100644
--- a/src/main/java/com/android/tools/r8/utils/RetracerForCodePrinting.java
+++ b/src/main/java/com/android/tools/r8/utils/RetracerForCodePrinting.java
@@ -24,6 +24,7 @@
 import com.android.tools.r8.retrace.Retracer;
 import com.android.tools.r8.retrace.internal.MappingSupplierInternalImpl;
 import com.android.tools.r8.retrace.internal.RetracerImpl;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.function.Function;
 
 public class RetracerForCodePrinting {
diff --git a/src/main/java/com/android/tools/r8/utils/SymbolGenerationUtils.java b/src/main/java/com/android/tools/r8/utils/SymbolGenerationUtils.java
index 7ef42c0..fe4db06 100644
--- a/src/main/java/com/android/tools/r8/utils/SymbolGenerationUtils.java
+++ b/src/main/java/com/android/tools/r8/utils/SymbolGenerationUtils.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.utils;
 
-import static com.android.tools.r8.utils.StringUtils.EMPTY_CHAR_ARRAY;
+import static com.android.tools.r8.utils.internal.StringUtils.EMPTY_CHAR_ARRAY;
 
 import com.google.common.collect.Sets;
 import java.util.Arrays;
diff --git a/src/main/java/com/android/tools/r8/utils/SystemPropertyUtils.java b/src/main/java/com/android/tools/r8/utils/SystemPropertyUtils.java
index df944be..006d649 100644
--- a/src/main/java/com/android/tools/r8/utils/SystemPropertyUtils.java
+++ b/src/main/java/com/android/tools/r8/utils/SystemPropertyUtils.java
@@ -8,6 +8,7 @@
 
 import com.android.tools.r8.Version;
 import com.android.tools.r8.utils.internal.OptionalBool;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import java.nio.file.Path;
 import java.nio.file.Paths;
diff --git a/src/main/java/com/android/tools/r8/utils/ZipUtils.java b/src/main/java/com/android/tools/r8/utils/ZipUtils.java
index a810960..4adff4f 100644
--- a/src/main/java/com/android/tools/r8/utils/ZipUtils.java
+++ b/src/main/java/com/android/tools/r8/utils/ZipUtils.java
@@ -3,9 +3,9 @@
 // BSD-style license that can be found in the LICENSE file.
 package com.android.tools.r8.utils;
 
-import static com.android.tools.r8.utils.FileUtils.CLASS_EXTENSION;
-import static com.android.tools.r8.utils.FileUtils.DEX_EXTENSION;
-import static com.android.tools.r8.utils.FileUtils.MODULE_INFO_CLASS;
+import static com.android.tools.r8.utils.internal.FileUtils.CLASS_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.DEX_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.MODULE_INFO_CLASS;
 
 import com.android.tools.r8.ByteDataView;
 import com.android.tools.r8.DataDirectoryResource;
@@ -17,6 +17,8 @@
 import com.android.tools.r8.references.ClassReference;
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.utils.internal.BooleanBox;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.io.ByteStreams;
 import com.google.common.io.Closer;
 import java.io.BufferedOutputStream;
diff --git a/src/test/bootstrap/com/android/tools/r8/bootstrap/BootstrapCurrentEqualityTest.java b/src/test/bootstrap/com/android/tools/r8/bootstrap/BootstrapCurrentEqualityTest.java
index 6e7b1f7..3273974 100644
--- a/src/test/bootstrap/com/android/tools/r8/bootstrap/BootstrapCurrentEqualityTest.java
+++ b/src/test/bootstrap/com/android/tools/r8/bootstrap/BootstrapCurrentEqualityTest.java
@@ -24,8 +24,8 @@
 import com.android.tools.r8.retrace.ProguardMappingSupplier;
 import com.android.tools.r8.retrace.Retrace;
 import com.android.tools.r8.retrace.RetraceCommand;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.collections.Pair;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Lists;
diff --git a/src/test/bootstrap/com/android/tools/r8/bootstrap/HelloWorldCompiledOnArtTest.java b/src/test/bootstrap/com/android/tools/r8/bootstrap/HelloWorldCompiledOnArtTest.java
index 1f89e1e..fc7f2d1 100644
--- a/src/test/bootstrap/com/android/tools/r8/bootstrap/HelloWorldCompiledOnArtTest.java
+++ b/src/test/bootstrap/com/android/tools/r8/bootstrap/HelloWorldCompiledOnArtTest.java
@@ -20,7 +20,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.DesugaredLibraryTestCompileResult;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.nio.file.Path;
diff --git a/src/test/bootstrap/com/android/tools/r8/bootstrap/JavaD8CompilationTest.java b/src/test/bootstrap/com/android/tools/r8/bootstrap/JavaD8CompilationTest.java
index 523d51f..b292ad5 100644
--- a/src/test/bootstrap/com/android/tools/r8/bootstrap/JavaD8CompilationTest.java
+++ b/src/test/bootstrap/com/android/tools/r8/bootstrap/JavaD8CompilationTest.java
@@ -4,8 +4,8 @@
 
 package com.android.tools.r8.bootstrap;
 
-import static com.android.tools.r8.utils.FileUtils.CLASS_EXTENSION;
 import static com.android.tools.r8.utils.InternalOptions.ASM_VERSION;
+import static com.android.tools.r8.utils.internal.FileUtils.CLASS_EXTENSION;
 import static junit.framework.TestCase.assertEquals;
 import static junit.framework.TestCase.assertTrue;
 import static junit.framework.TestCase.fail;
diff --git a/src/test/bootstrap/com/android/tools/r8/bootstrap/RetraceStackTraceFunctionalCompositionTest.java b/src/test/bootstrap/com/android/tools/r8/bootstrap/RetraceStackTraceFunctionalCompositionTest.java
index b91bebd..13b251c 100644
--- a/src/test/bootstrap/com/android/tools/r8/bootstrap/RetraceStackTraceFunctionalCompositionTest.java
+++ b/src/test/bootstrap/com/android/tools/r8/bootstrap/RetraceStackTraceFunctionalCompositionTest.java
@@ -23,11 +23,11 @@
 import com.android.tools.r8.transformers.ClassTransformer;
 import com.android.tools.r8.transformers.MethodTransformer;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.internal.Box;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.StackTraceUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.ZipUtils;
+import com.android.tools.r8.utils.internal.Box;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.collections.Pair;
 import com.google.common.collect.ImmutableList;
 import java.io.File;
diff --git a/src/test/bootstrap/com/android/tools/r8/bootstrap/SanityCheck.java b/src/test/bootstrap/com/android/tools/r8/bootstrap/SanityCheck.java
index 46bd678..06637c7 100644
--- a/src/test/bootstrap/com/android/tools/r8/bootstrap/SanityCheck.java
+++ b/src/test/bootstrap/com/android/tools/r8/bootstrap/SanityCheck.java
@@ -5,7 +5,7 @@
 package com.android.tools.r8.bootstrap;
 
 import static com.android.tools.r8.utils.DescriptorUtils.JAVA_PACKAGE_SEPARATOR;
-import static com.android.tools.r8.utils.FileUtils.JAVA_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.JAVA_EXTENSION;
 import static org.hamcrest.CoreMatchers.startsWith;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.junit.Assert.assertEquals;
@@ -21,11 +21,11 @@
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.Version;
 import com.android.tools.r8.naming.ClassNameMapper;
-import com.android.tools.r8.utils.internal.BooleanBox;
 import com.android.tools.r8.utils.CfUtils;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.internal.StreamUtils;
 import com.android.tools.r8.utils.ZipUtils;
+import com.android.tools.r8.utils.internal.BooleanBox;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StreamUtils;
 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Sets;
 import java.io.IOException;
diff --git a/src/test/bootstrap/com/android/tools/r8/bootstrap/WhyAreYouKeepingAllTest.java b/src/test/bootstrap/com/android/tools/r8/bootstrap/WhyAreYouKeepingAllTest.java
index 78e6be3..a8e4725 100644
--- a/src/test/bootstrap/com/android/tools/r8/bootstrap/WhyAreYouKeepingAllTest.java
+++ b/src/test/bootstrap/com/android/tools/r8/bootstrap/WhyAreYouKeepingAllTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ToolHelper;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Path;
 import java.nio.file.Paths;
diff --git a/src/test/java/com/android/tools/r8/B379241435InterfaceInitializedAftertInstantiatingImplementorTest.java b/src/test/java/com/android/tools/r8/B379241435InterfaceInitializedAftertInstantiatingImplementorTest.java
index 141ba96..b5c0001 100644
--- a/src/test/java/com/android/tools/r8/B379241435InterfaceInitializedAftertInstantiatingImplementorTest.java
+++ b/src/test/java/com/android/tools/r8/B379241435InterfaceInitializedAftertInstantiatingImplementorTest.java
@@ -3,7 +3,7 @@
 // BSD-style license that can be found in the LICENSE file.
 package com.android.tools.r8;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/B379241435InterfaceInitializedFromImplementorStaticMethodTest.java b/src/test/java/com/android/tools/r8/B379241435InterfaceInitializedFromImplementorStaticMethodTest.java
index bb43551..35cc43b 100644
--- a/src/test/java/com/android/tools/r8/B379241435InterfaceInitializedFromImplementorStaticMethodTest.java
+++ b/src/test/java/com/android/tools/r8/B379241435InterfaceInitializedFromImplementorStaticMethodTest.java
@@ -3,7 +3,7 @@
 // BSD-style license that can be found in the LICENSE file.
 package com.android.tools.r8;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/B379241435InterfaceInitializedFromImplementorVirtualMethodTest.java b/src/test/java/com/android/tools/r8/B379241435InterfaceInitializedFromImplementorVirtualMethodTest.java
index bdb3b3b..f90de0d 100644
--- a/src/test/java/com/android/tools/r8/B379241435InterfaceInitializedFromImplementorVirtualMethodTest.java
+++ b/src/test/java/com/android/tools/r8/B379241435InterfaceInitializedFromImplementorVirtualMethodTest.java
@@ -3,7 +3,7 @@
 // BSD-style license that can be found in the LICENSE file.
 package com.android.tools.r8;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/B419404081Test.java b/src/test/java/com/android/tools/r8/B419404081Test.java
index c89552a..b88713b 100644
--- a/src/test/java/com/android/tools/r8/B419404081Test.java
+++ b/src/test/java/com/android/tools/r8/B419404081Test.java
@@ -7,7 +7,7 @@
 
 import com.android.tools.r8.B419404081Test.Cr.Ci_abs_sta;
 import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/CommandTestBase.java b/src/test/java/com/android/tools/r8/CommandTestBase.java
index 01fa368..7f6c0bd 100644
--- a/src/test/java/com/android/tools/r8/CommandTestBase.java
+++ b/src/test/java/com/android/tools/r8/CommandTestBase.java
@@ -18,10 +18,10 @@
 import com.android.tools.r8.startup.StartupProfileProvider;
 import com.android.tools.r8.startup.diagnostic.MissingStartupProfileItemsDiagnostic;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.internal.IntBox;
 import com.android.tools.r8.utils.InternalOptions;
 import com.android.tools.r8.utils.ListUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.IntBox;
 import com.android.tools.r8.utils.timing.Timing;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
diff --git a/src/test/java/com/android/tools/r8/D8CommandTest.java b/src/test/java/com/android/tools/r8/D8CommandTest.java
index c5e9086..83fa844 100644
--- a/src/test/java/com/android/tools/r8/D8CommandTest.java
+++ b/src/test/java/com/android/tools/r8/D8CommandTest.java
@@ -3,15 +3,12 @@
 // BSD-style license that can be found in the LICENSE file.
 package com.android.tools.r8;
 
-import static com.android.tools.r8.DiagnosticsMatcher.diagnosticMessage;
 import static com.android.tools.r8.R8CommandTest.getOutputPath;
 import static com.android.tools.r8.ToolHelper.EXAMPLES_BUILD_DIR;
-import static com.android.tools.r8.utils.FileUtils.JAR_EXTENSION;
-import static org.hamcrest.CoreMatchers.containsString;
+import static com.android.tools.r8.utils.internal.FileUtils.JAR_EXTENSION;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertNotEquals;
-import static org.junit.Assert.assertSame;
 import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.fail;
 
@@ -28,10 +25,10 @@
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.AndroidApp;
 import com.android.tools.r8.utils.ExtractMarkerUtils;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.InternalOptions;
 import com.android.tools.r8.utils.ThreadUtils;
 import com.android.tools.r8.utils.ZipUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.nio.charset.StandardCharsets;
diff --git a/src/test/java/com/android/tools/r8/D8IncrementalRunExamplesAndroidOTest.java b/src/test/java/com/android/tools/r8/D8IncrementalRunExamplesAndroidOTest.java
index 00ade22..cfbd236 100644
--- a/src/test/java/com/android/tools/r8/D8IncrementalRunExamplesAndroidOTest.java
+++ b/src/test/java/com/android/tools/r8/D8IncrementalRunExamplesAndroidOTest.java
@@ -5,7 +5,7 @@
 package com.android.tools.r8;
 
 import static com.android.tools.r8.ir.desugar.itf.InterfaceDesugaringForTesting.getCompanionClassNameSuffix;
-import static com.android.tools.r8.utils.FileUtils.JAR_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.JAR_EXTENSION;
 import static org.junit.Assert.assertEquals;
 
 import com.android.tools.r8.Disassemble.DisassembleCommand;
@@ -13,11 +13,11 @@
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.internal.Box;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.OffOrAuto;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.Box;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import com.google.common.collect.Lists;
 import com.google.common.io.ByteStreams;
diff --git a/src/test/java/com/android/tools/r8/D8LazyRunExamplesAndroidOTest.java b/src/test/java/com/android/tools/r8/D8LazyRunExamplesAndroidOTest.java
index 91f396c..adf392c 100644
--- a/src/test/java/com/android/tools/r8/D8LazyRunExamplesAndroidOTest.java
+++ b/src/test/java/com/android/tools/r8/D8LazyRunExamplesAndroidOTest.java
@@ -4,14 +4,14 @@
 
 package com.android.tools.r8;
 
-import static com.android.tools.r8.utils.FileUtils.JAR_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.JAR_EXTENSION;
 import static org.junit.Assert.assertTrue;
 
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.AndroidApp;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.OffOrAuto;
 import com.android.tools.r8.utils.ZipUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/ExtractMarkerTest.java b/src/test/java/com/android/tools/r8/ExtractMarkerTest.java
index b8baf23..0d5c8f4 100644
--- a/src/test/java/com/android/tools/r8/ExtractMarkerTest.java
+++ b/src/test/java/com/android/tools/r8/ExtractMarkerTest.java
@@ -11,9 +11,9 @@
 import com.android.tools.r8.dex.Marker.Tool;
 import com.android.tools.r8.graph.DexItemFactory;
 import com.android.tools.r8.graph.DexString;
-import com.android.tools.r8.utils.internal.BooleanUtils;
 import com.android.tools.r8.utils.ExtractMarkerUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.Collection;
 import java.util.Set;
diff --git a/src/test/java/com/android/tools/r8/FailCompilationOnFutureVersionsTest.java b/src/test/java/com/android/tools/r8/FailCompilationOnFutureVersionsTest.java
index b1ebaf3..ad4b1e4 100644
--- a/src/test/java/com/android/tools/r8/FailCompilationOnFutureVersionsTest.java
+++ b/src/test/java/com/android/tools/r8/FailCompilationOnFutureVersionsTest.java
@@ -9,7 +9,7 @@
 import static org.junit.Assert.fail;
 
 import com.android.tools.r8.utils.InternalOptions;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.nio.file.Path;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/JunitAvailabilityInHostArtTest.java b/src/test/java/com/android/tools/r8/JunitAvailabilityInHostArtTest.java
index 29d0132..e6c1ee2 100644
--- a/src/test/java/com/android/tools/r8/JunitAvailabilityInHostArtTest.java
+++ b/src/test/java/com/android/tools/r8/JunitAvailabilityInHostArtTest.java
@@ -8,7 +8,7 @@
 import static org.junit.Assume.assumeTrue;
 
 import com.android.tools.r8.ToolHelper.DexVm;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/L8CommandTest.java b/src/test/java/com/android/tools/r8/L8CommandTest.java
index 5272775..593c434 100644
--- a/src/test/java/com/android/tools/r8/L8CommandTest.java
+++ b/src/test/java/com/android/tools/r8/L8CommandTest.java
@@ -23,9 +23,9 @@
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.utils.ExtractMarkerUtils;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.InternalOptions;
 import com.android.tools.r8.utils.ThreadUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.nio.charset.StandardCharsets;
diff --git a/src/test/java/com/android/tools/r8/MarkersTest.java b/src/test/java/com/android/tools/r8/MarkersTest.java
index ee02097..88eff76 100644
--- a/src/test/java/com/android/tools/r8/MarkersTest.java
+++ b/src/test/java/com/android/tools/r8/MarkersTest.java
@@ -27,9 +27,9 @@
 import com.android.tools.r8.dex.Marker.Tool;
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.internal.BooleanUtils;
 import com.android.tools.r8.utils.ExtractMarkerUtils;
-import com.android.tools.r8.utils.FileUtils;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.base.Charsets;
 import com.google.common.collect.ImmutableList;
 import com.google.gson.JsonObject;
diff --git a/src/test/java/com/android/tools/r8/R8CFRunExamplesJava9Test.java b/src/test/java/com/android/tools/r8/R8CFRunExamplesJava9Test.java
index 050fe1c..ce4a1d9 100644
--- a/src/test/java/com/android/tools/r8/R8CFRunExamplesJava9Test.java
+++ b/src/test/java/com/android/tools/r8/R8CFRunExamplesJava9Test.java
@@ -4,14 +4,14 @@
 
 package com.android.tools.r8;
 
-import static com.android.tools.r8.utils.FileUtils.ZIP_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.ZIP_EXTENSION;
 import static org.junit.Assert.assertEquals;
 
 import com.android.tools.r8.ToolHelper.ProcessResult;
 import com.android.tools.r8.desugar.LibraryFilesHelper;
 import com.android.tools.r8.origin.Origin;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/R8CommandTest.java b/src/test/java/com/android/tools/r8/R8CommandTest.java
index 37488a8..57e1b7b 100644
--- a/src/test/java/com/android/tools/r8/R8CommandTest.java
+++ b/src/test/java/com/android/tools/r8/R8CommandTest.java
@@ -3,14 +3,11 @@
 // BSD-style license that can be found in the LICENSE file.
 package com.android.tools.r8;
 
-import static com.android.tools.r8.DiagnosticsMatcher.diagnosticMessage;
 import static com.android.tools.r8.ToolHelper.EXAMPLES_BUILD_DIR;
-import static org.hamcrest.CoreMatchers.containsString;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertNotEquals;
 import static org.junit.Assert.assertNotNull;
-import static org.junit.Assert.assertSame;
 import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.fail;
 
@@ -27,10 +24,10 @@
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.ExtractMarkerUtils;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.InternalOptions;
 import com.android.tools.r8.utils.ThreadUtils;
 import com.android.tools.r8.utils.ZipUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.File;
 import java.io.IOException;
diff --git a/src/test/java/com/android/tools/r8/R8EntryPointTests.java b/src/test/java/com/android/tools/r8/R8EntryPointTests.java
index 72438ac..d3aac14 100644
--- a/src/test/java/com/android/tools/r8/R8EntryPointTests.java
+++ b/src/test/java/com/android/tools/r8/R8EntryPointTests.java
@@ -8,7 +8,7 @@
 import static org.hamcrest.core.StringContains.containsString;
 
 import com.android.tools.r8.ToolHelper.ProcessResult;
-import com.android.tools.r8.utils.FileUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.nio.file.Files;
diff --git a/src/test/java/com/android/tools/r8/R8RunExamplesAndroidOTest.java b/src/test/java/com/android/tools/r8/R8RunExamplesAndroidOTest.java
index 6013e4a..ac808a8 100644
--- a/src/test/java/com/android/tools/r8/R8RunExamplesAndroidOTest.java
+++ b/src/test/java/com/android/tools/r8/R8RunExamplesAndroidOTest.java
@@ -12,14 +12,14 @@
 import com.android.tools.r8.VmTestRunner.IgnoreIfVmOlderThan;
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.internal.Box;
 import com.android.tools.r8.utils.OffOrAuto;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FoundClassSubject;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.Box;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
diff --git a/src/test/java/com/android/tools/r8/R8RunExamplesTestBase.java b/src/test/java/com/android/tools/r8/R8RunExamplesTestBase.java
index 2c6ab41..5981a5e 100644
--- a/src/test/java/com/android/tools/r8/R8RunExamplesTestBase.java
+++ b/src/test/java/com/android/tools/r8/R8RunExamplesTestBase.java
@@ -3,7 +3,7 @@
 // BSD-style license that can be found in the LICENSE file.
 package com.android.tools.r8;
 
-import static com.android.tools.r8.utils.FileUtils.JAR_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.JAR_EXTENSION;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.fail;
diff --git a/src/test/java/com/android/tools/r8/R8RunSmaliTestsTest.java b/src/test/java/com/android/tools/r8/R8RunSmaliTestsTest.java
index cd24893..af02df7 100644
--- a/src/test/java/com/android/tools/r8/R8RunSmaliTestsTest.java
+++ b/src/test/java/com/android/tools/r8/R8RunSmaliTestsTest.java
@@ -7,8 +7,8 @@
 
 import com.android.tools.r8.ToolHelper.DexVm;
 import com.android.tools.r8.ToolHelper.DexVm.Version;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.TestDescriptionWatcher;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.ImmutableSet;
diff --git a/src/test/java/com/android/tools/r8/RegressionForPrimitiveDefinitionForLookup.java b/src/test/java/com/android/tools/r8/RegressionForPrimitiveDefinitionForLookup.java
index b43bb8b..bafc654 100644
--- a/src/test/java/com/android/tools/r8/RegressionForPrimitiveDefinitionForLookup.java
+++ b/src/test/java/com/android/tools/r8/RegressionForPrimitiveDefinitionForLookup.java
@@ -3,7 +3,7 @@
 // BSD-style license that can be found in the LICENSE file.
 package com.android.tools.r8;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 
 class Tester {
diff --git a/src/test/java/com/android/tools/r8/RunExamplesAndroidNTest.java b/src/test/java/com/android/tools/r8/RunExamplesAndroidNTest.java
index 4154c30..5ae6f25 100644
--- a/src/test/java/com/android/tools/r8/RunExamplesAndroidNTest.java
+++ b/src/test/java/com/android/tools/r8/RunExamplesAndroidNTest.java
@@ -4,8 +4,8 @@
 
 package com.android.tools.r8;
 
-import static com.android.tools.r8.utils.FileUtils.JAR_EXTENSION;
-import static com.android.tools.r8.utils.FileUtils.ZIP_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.JAR_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.ZIP_EXTENSION;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertTrue;
 
diff --git a/src/test/java/com/android/tools/r8/RunExamplesAndroidOTest.java b/src/test/java/com/android/tools/r8/RunExamplesAndroidOTest.java
index 15edfef..c256b93 100644
--- a/src/test/java/com/android/tools/r8/RunExamplesAndroidOTest.java
+++ b/src/test/java/com/android/tools/r8/RunExamplesAndroidOTest.java
@@ -4,8 +4,8 @@
 
 package com.android.tools.r8;
 
-import static com.android.tools.r8.utils.FileUtils.JAR_EXTENSION;
-import static com.android.tools.r8.utils.FileUtils.ZIP_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.JAR_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.ZIP_EXTENSION;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertNotEquals;
@@ -20,18 +20,18 @@
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.AndroidApp;
-import com.android.tools.r8.utils.internal.Box;
 import com.android.tools.r8.utils.InternalOptions;
 import com.android.tools.r8.utils.ListUtils;
 import com.android.tools.r8.utils.OffOrAuto;
-import com.android.tools.r8.utils.StringUtils;
-import com.android.tools.r8.utils.StringUtils.BraceType;
 import com.android.tools.r8.utils.TestDescriptionWatcher;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FoundClassSubject;
 import com.android.tools.r8.utils.codeinspector.FoundMethodSubject;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.InvokeInstructionSubject;
+import com.android.tools.r8.utils.internal.Box;
+import com.android.tools.r8.utils.internal.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils.BraceType;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.Lists;
diff --git a/src/test/java/com/android/tools/r8/RunExamplesAndroidPTest.java b/src/test/java/com/android/tools/r8/RunExamplesAndroidPTest.java
index 6c1a1de..56c4ec1 100644
--- a/src/test/java/com/android/tools/r8/RunExamplesAndroidPTest.java
+++ b/src/test/java/com/android/tools/r8/RunExamplesAndroidPTest.java
@@ -4,8 +4,8 @@
 
 package com.android.tools.r8;
 
-import static com.android.tools.r8.utils.FileUtils.JAR_EXTENSION;
-import static com.android.tools.r8.utils.FileUtils.ZIP_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.JAR_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.ZIP_EXTENSION;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertTrue;
 
diff --git a/src/test/java/com/android/tools/r8/RunExamplesJava9Test.java b/src/test/java/com/android/tools/r8/RunExamplesJava9Test.java
index 011d567..4f27ef9 100644
--- a/src/test/java/com/android/tools/r8/RunExamplesJava9Test.java
+++ b/src/test/java/com/android/tools/r8/RunExamplesJava9Test.java
@@ -6,9 +6,9 @@
 
 import static com.android.tools.r8.ir.desugar.itf.InterfaceDesugaringForTesting.getCompanionClassNameSuffix;
 import static com.android.tools.r8.ir.desugar.itf.InterfaceDesugaringForTesting.getPrivateMethodPrefix;
-import static com.android.tools.r8.utils.FileUtils.JAR_EXTENSION;
-import static com.android.tools.r8.utils.FileUtils.ZIP_EXTENSION;
 import static com.android.tools.r8.utils.codeinspector.Matchers.isPresent;
+import static com.android.tools.r8.utils.internal.FileUtils.JAR_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.ZIP_EXTENSION;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertTrue;
diff --git a/src/test/java/com/android/tools/r8/accessrelaxation/ConstructorRelaxationTest.java b/src/test/java/com/android/tools/r8/accessrelaxation/ConstructorRelaxationTest.java
index f2ca6d3..9bba77a 100644
--- a/src/test/java/com/android/tools/r8/accessrelaxation/ConstructorRelaxationTest.java
+++ b/src/test/java/com/android/tools/r8/accessrelaxation/ConstructorRelaxationTest.java
@@ -11,9 +11,9 @@
 import com.android.tools.r8.R8TestRunResult;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/accessrelaxation/NoRelaxationForSerializableTest.java b/src/test/java/com/android/tools/r8/accessrelaxation/NoRelaxationForSerializableTest.java
index 96ede0e..5174c29 100644
--- a/src/test/java/com/android/tools/r8/accessrelaxation/NoRelaxationForSerializableTest.java
+++ b/src/test/java/com/android/tools/r8/accessrelaxation/NoRelaxationForSerializableTest.java
@@ -15,9 +15,9 @@
 import com.android.tools.r8.ToolHelper.DexVm.Version;
 import com.android.tools.r8.naming.MemberNaming.MethodSignature;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.ByteArrayInputStream;
 import java.io.ByteArrayOutputStream;
diff --git a/src/test/java/com/android/tools/r8/accessrelaxation/NonConstructorRelaxationTest.java b/src/test/java/com/android/tools/r8/accessrelaxation/NonConstructorRelaxationTest.java
index 6ff50e0..7f2b62a 100644
--- a/src/test/java/com/android/tools/r8/accessrelaxation/NonConstructorRelaxationTest.java
+++ b/src/test/java/com/android/tools/r8/accessrelaxation/NonConstructorRelaxationTest.java
@@ -18,9 +18,9 @@
 import com.android.tools.r8.accessrelaxation.privatestatic.BB;
 import com.android.tools.r8.accessrelaxation.privatestatic.C;
 import com.android.tools.r8.naming.MemberNaming.MethodSignature;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/accessrelaxation/PrivateOverrideOfPublicMethodTest.java b/src/test/java/com/android/tools/r8/accessrelaxation/PrivateOverrideOfPublicMethodTest.java
index 40f0c83..e452e9e 100644
--- a/src/test/java/com/android/tools/r8/accessrelaxation/PrivateOverrideOfPublicMethodTest.java
+++ b/src/test/java/com/android/tools/r8/accessrelaxation/PrivateOverrideOfPublicMethodTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ToolHelper.DexVm.Version;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import org.junit.BeforeClass;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/accessrelaxation/PublicOverrideOfPrivateMethodTest.java b/src/test/java/com/android/tools/r8/accessrelaxation/PublicOverrideOfPrivateMethodTest.java
index 09d3456..1cd1e39 100644
--- a/src/test/java/com/android/tools/r8/accessrelaxation/PublicOverrideOfPrivateMethodTest.java
+++ b/src/test/java/com/android/tools/r8/accessrelaxation/PublicOverrideOfPrivateMethodTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/androidapi/AndroidJarMasterTest.java b/src/test/java/com/android/tools/r8/androidapi/AndroidJarMasterTest.java
index 0b0b108..3843071 100644
--- a/src/test/java/com/android/tools/r8/androidapi/AndroidJarMasterTest.java
+++ b/src/test/java/com/android/tools/r8/androidapi/AndroidJarMasterTest.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/androidapi/AndroidJarSv2Test.java b/src/test/java/com/android/tools/r8/androidapi/AndroidJarSv2Test.java
index 4fcbba4..71a9f7b 100644
--- a/src/test/java/com/android/tools/r8/androidapi/AndroidJarSv2Test.java
+++ b/src/test/java/com/android/tools/r8/androidapi/AndroidJarSv2Test.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/androidapi/AndroidJarTTest.java b/src/test/java/com/android/tools/r8/androidapi/AndroidJarTTest.java
index edb5641..7d7af1b 100644
--- a/src/test/java/com/android/tools/r8/androidapi/AndroidJarTTest.java
+++ b/src/test/java/com/android/tools/r8/androidapi/AndroidJarTTest.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/androidapi/GenerateAvailableApiExceptions.java b/src/test/java/com/android/tools/r8/androidapi/GenerateAvailableApiExceptions.java
index fc1629b..8a1c6b1 100644
--- a/src/test/java/com/android/tools/r8/androidapi/GenerateAvailableApiExceptions.java
+++ b/src/test/java/com/android/tools/r8/androidapi/GenerateAvailableApiExceptions.java
@@ -8,9 +8,9 @@
 import com.android.tools.r8.graph.DexClass;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.FileUtils;
 import it.unimi.dsi.fastutil.ints.Int2ReferenceMap;
 import it.unimi.dsi.fastutil.ints.Int2ReferenceOpenHashMap;
 import java.nio.file.Files;
diff --git a/src/test/java/com/android/tools/r8/androidapi/GenerateCovariantReturnTypeMethodsTest.java b/src/test/java/com/android/tools/r8/androidapi/GenerateCovariantReturnTypeMethodsTest.java
index 4e89b2a..fb89215 100644
--- a/src/test/java/com/android/tools/r8/androidapi/GenerateCovariantReturnTypeMethodsTest.java
+++ b/src/test/java/com/android/tools/r8/androidapi/GenerateCovariantReturnTypeMethodsTest.java
@@ -30,14 +30,14 @@
 import com.android.tools.r8.references.MethodReference;
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.references.TypeReference;
-import com.android.tools.r8.utils.internal.Action;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.ClassReferenceUtils;
-import com.android.tools.r8.utils.internal.EntryUtils;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.MethodReferenceUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FoundClassSubject;
+import com.android.tools.r8.utils.internal.Action;
+import com.android.tools.r8.utils.internal.EntryUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
diff --git a/src/test/java/com/android/tools/r8/androidresources/ManifestPruningTest.java b/src/test/java/com/android/tools/r8/androidresources/ManifestPruningTest.java
index 9622884..5633f95 100644
--- a/src/test/java/com/android/tools/r8/androidresources/ManifestPruningTest.java
+++ b/src/test/java/com/android/tools/r8/androidresources/ManifestPruningTest.java
@@ -15,9 +15,9 @@
 import com.android.tools.r8.androidresources.AndroidResourceTestingUtils.AndroidTestResourceBuilder;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.AndroidApp;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import java.nio.file.Path;
 import java.util.ArrayList;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/androidresources/SimpleNoCodeReferenceAndroidResourceTest.java b/src/test/java/com/android/tools/r8/androidresources/SimpleNoCodeReferenceAndroidResourceTest.java
index f26b2ab..1462792 100644
--- a/src/test/java/com/android/tools/r8/androidresources/SimpleNoCodeReferenceAndroidResourceTest.java
+++ b/src/test/java/com/android/tools/r8/androidresources/SimpleNoCodeReferenceAndroidResourceTest.java
@@ -16,9 +16,9 @@
 import com.android.tools.r8.androidresources.AndroidResourceTestingUtils.AndroidTestResource;
 import com.android.tools.r8.androidresources.AndroidResourceTestingUtils.AndroidTestResourceBuilder;
 import com.android.tools.r8.androidresources.AndroidResourceTestingUtils.ResourceTableInspector;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.ZipUtils;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import java.io.IOException;
 import java.nio.charset.Charset;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/annotations/AnnotationWithInjectedMethodsTest.java b/src/test/java/com/android/tools/r8/annotations/AnnotationWithInjectedMethodsTest.java
index 77f22c9..b45d4fa 100644
--- a/src/test/java/com/android/tools/r8/annotations/AnnotationWithInjectedMethodsTest.java
+++ b/src/test/java/com/android/tools/r8/annotations/AnnotationWithInjectedMethodsTest.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ToolHelper.DexVm.Version;
 import com.android.tools.r8.enumunboxing.EnumUnboxingTestBase;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.lang.annotation.Annotation;
diff --git a/src/test/java/com/android/tools/r8/annotations/DefaultAnnotationTest.java b/src/test/java/com/android/tools/r8/annotations/DefaultAnnotationTest.java
index b02af88..41325e8 100644
--- a/src/test/java/com/android/tools/r8/annotations/DefaultAnnotationTest.java
+++ b/src/test/java/com/android/tools/r8/annotations/DefaultAnnotationTest.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.ThrowableConsumer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.lang.annotation.Annotation;
 import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
diff --git a/src/test/java/com/android/tools/r8/annotations/NestedAnnotationsUnusedTest.java b/src/test/java/com/android/tools/r8/annotations/NestedAnnotationsUnusedTest.java
index a807a27..3df6a12 100644
--- a/src/test/java/com/android/tools/r8/annotations/NestedAnnotationsUnusedTest.java
+++ b/src/test/java/com/android/tools/r8/annotations/NestedAnnotationsUnusedTest.java
@@ -10,9 +10,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.annotations.NestedAnnotationsUsedTest.A;
-import com.android.tools.r8.annotations.NestedAnnotationsUsedTest.TestClass;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
diff --git a/src/test/java/com/android/tools/r8/annotations/NestedAnnotationsUsedTest.java b/src/test/java/com/android/tools/r8/annotations/NestedAnnotationsUsedTest.java
index 90ae5bf..f300446 100644
--- a/src/test/java/com/android/tools/r8/annotations/NestedAnnotationsUsedTest.java
+++ b/src/test/java/com/android/tools/r8/annotations/NestedAnnotationsUsedTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
diff --git a/src/test/java/com/android/tools/r8/annotations/RetentionPolicyTest.java b/src/test/java/com/android/tools/r8/annotations/RetentionPolicyTest.java
index bafe509..13bed30 100644
--- a/src/test/java/com/android/tools/r8/annotations/RetentionPolicyTest.java
+++ b/src/test/java/com/android/tools/r8/annotations/RetentionPolicyTest.java
@@ -13,10 +13,10 @@
 import com.android.tools.r8.D8TestCompileResult;
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.lang.annotation.Annotation;
 import java.lang.annotation.Retention;
diff --git a/src/test/java/com/android/tools/r8/annotations/TypeUseAnnotationPruneTest.java b/src/test/java/com/android/tools/r8/annotations/TypeUseAnnotationPruneTest.java
index 3a72818..e10c986 100644
--- a/src/test/java/com/android/tools/r8/annotations/TypeUseAnnotationPruneTest.java
+++ b/src/test/java/com/android/tools/r8/annotations/TypeUseAnnotationPruneTest.java
@@ -18,11 +18,11 @@
 import com.android.tools.r8.annotations.testclasses.NotNullTestRuntime;
 import com.android.tools.r8.annotations.testclasses.SuperInterface;
 import com.android.tools.r8.annotations.testclasses.TestClassWithTypeAndGenericAnnotations;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.FieldSubject;
 import com.android.tools.r8.utils.codeinspector.FoundAnnotationSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.lang.reflect.AnnotatedType;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/annotations/TypeUseAnnotationWithGenericsTest.java b/src/test/java/com/android/tools/r8/annotations/TypeUseAnnotationWithGenericsTest.java
index 341f074..98a33fe 100644
--- a/src/test/java/com/android/tools/r8/annotations/TypeUseAnnotationWithGenericsTest.java
+++ b/src/test/java/com/android/tools/r8/annotations/TypeUseAnnotationWithGenericsTest.java
@@ -21,12 +21,12 @@
 import com.android.tools.r8.annotations.testclasses.SuperInterface;
 import com.android.tools.r8.annotations.testclasses.TestClassWithTypeAndGenericAnnotations;
 import com.android.tools.r8.references.ClassReference;
-import com.android.tools.r8.utils.internal.Box;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.FieldSubject;
 import com.android.tools.r8.utils.codeinspector.FoundAnnotationSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.Box;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.lang.reflect.AnnotatedType;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/apimodel/AndroidApiHashingDatabaseBuilderGeneratorTest.java b/src/test/java/com/android/tools/r8/apimodel/AndroidApiHashingDatabaseBuilderGeneratorTest.java
index 774974e..c2bf2fa 100644
--- a/src/test/java/com/android/tools/r8/apimodel/AndroidApiHashingDatabaseBuilderGeneratorTest.java
+++ b/src/test/java/com/android/tools/r8/apimodel/AndroidApiHashingDatabaseBuilderGeneratorTest.java
@@ -37,10 +37,10 @@
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.AndroidApp;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.internal.IntBox;
 import com.android.tools.r8.utils.InternalOptions;
 import com.android.tools.r8.utils.ZipUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.IntBox;
 import com.android.tools.r8.utils.timing.Timing;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Files;
diff --git a/src/test/java/com/android/tools/r8/apimodel/ApiModelBridgeToLibraryMethodTest.java b/src/test/java/com/android/tools/r8/apimodel/ApiModelBridgeToLibraryMethodTest.java
index 28d5037..a1f3c81 100644
--- a/src/test/java/com/android/tools/r8/apimodel/ApiModelBridgeToLibraryMethodTest.java
+++ b/src/test/java/com/android/tools/r8/apimodel/ApiModelBridgeToLibraryMethodTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.testing.AndroidBuildVersion;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.function.Function;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/apimodel/ApiModelExcludeClinitOutliningInSynchronizedMethodTest.java b/src/test/java/com/android/tools/r8/apimodel/ApiModelExcludeClinitOutliningInSynchronizedMethodTest.java
index 6ce6597..e894e64 100644
--- a/src/test/java/com/android/tools/r8/apimodel/ApiModelExcludeClinitOutliningInSynchronizedMethodTest.java
+++ b/src/test/java/com/android/tools/r8/apimodel/ApiModelExcludeClinitOutliningInSynchronizedMethodTest.java
@@ -12,10 +12,10 @@
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/apimodel/ApiModelExcludeClinitOutliningWhereArgumentsCouldCauseSideEffectsTest.java b/src/test/java/com/android/tools/r8/apimodel/ApiModelExcludeClinitOutliningWhereArgumentsCouldCauseSideEffectsTest.java
index 877ca72..cb1db2d 100644
--- a/src/test/java/com/android/tools/r8/apimodel/ApiModelExcludeClinitOutliningWhereArgumentsCouldCauseSideEffectsTest.java
+++ b/src/test/java/com/android/tools/r8/apimodel/ApiModelExcludeClinitOutliningWhereArgumentsCouldCauseSideEffectsTest.java
@@ -12,10 +12,10 @@
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/apimodel/ApiModelNoInliningOfLambdaTest.java b/src/test/java/com/android/tools/r8/apimodel/ApiModelNoInliningOfLambdaTest.java
index 7c944fd..a6d9f46 100644
--- a/src/test/java/com/android/tools/r8/apimodel/ApiModelNoInliningOfLambdaTest.java
+++ b/src/test/java/com/android/tools/r8/apimodel/ApiModelNoInliningOfLambdaTest.java
@@ -13,10 +13,10 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeMatchers;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.lang.reflect.Method;
 import org.junit.Assume;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/apimodel/ApiModelNoOutlineForFullyMockedTest.java b/src/test/java/com/android/tools/r8/apimodel/ApiModelNoOutlineForFullyMockedTest.java
index 8b49c23..0199525 100644
--- a/src/test/java/com/android/tools/r8/apimodel/ApiModelNoOutlineForFullyMockedTest.java
+++ b/src/test/java/com/android/tools/r8/apimodel/ApiModelNoOutlineForFullyMockedTest.java
@@ -21,8 +21,8 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.testing.AndroidBuildVersion;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.lang.reflect.Method;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/apimodel/ApiModelOutlineMethodExtensionApiMultipleExtensionPackagesTest.java b/src/test/java/com/android/tools/r8/apimodel/ApiModelOutlineMethodExtensionApiMultipleExtensionPackagesTest.java
index 5db9958..d729843 100644
--- a/src/test/java/com/android/tools/r8/apimodel/ApiModelOutlineMethodExtensionApiMultipleExtensionPackagesTest.java
+++ b/src/test/java/com/android/tools/r8/apimodel/ApiModelOutlineMethodExtensionApiMultipleExtensionPackagesTest.java
@@ -15,9 +15,9 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.apimodel.another_extension.AnotherExtensionApiLibraryClass;
 import com.android.tools.r8.apimodel.extension.ExtensionApiLibraryClass;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Path;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/apimodel/ApiModelOutlineMethodExtensionApiSubpackageTest.java b/src/test/java/com/android/tools/r8/apimodel/ApiModelOutlineMethodExtensionApiSubpackageTest.java
index 9e681cc..bb5d198 100644
--- a/src/test/java/com/android/tools/r8/apimodel/ApiModelOutlineMethodExtensionApiSubpackageTest.java
+++ b/src/test/java/com/android/tools/r8/apimodel/ApiModelOutlineMethodExtensionApiSubpackageTest.java
@@ -16,9 +16,9 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.apimodel.extension.ExtensionApiLibraryClass;
 import com.android.tools.r8.apimodel.extension.subpackage.SubpackageExtensionApiLibraryClass;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.List;
 import org.junit.BeforeClass;
diff --git a/src/test/java/com/android/tools/r8/apimodel/ApiModelOutlineMethodExtensionApiTest.java b/src/test/java/com/android/tools/r8/apimodel/ApiModelOutlineMethodExtensionApiTest.java
index 52ca5a2..6edede4 100644
--- a/src/test/java/com/android/tools/r8/apimodel/ApiModelOutlineMethodExtensionApiTest.java
+++ b/src/test/java/com/android/tools/r8/apimodel/ApiModelOutlineMethodExtensionApiTest.java
@@ -18,9 +18,9 @@
 import com.android.tools.r8.apimodel.extension.ExtensionApiLibraryInterface;
 import com.android.tools.r8.apimodel.extension.ExtensionApiLibraryInterfaceImpl;
 import com.android.tools.r8.apimodel.extension.ExtensionApiLibraryInterfaceProvider;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Path;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/apimodel/ClassValueTest.java b/src/test/java/com/android/tools/r8/apimodel/ClassValueTest.java
index f247e38..ec4d56d 100644
--- a/src/test/java/com/android/tools/r8/apimodel/ClassValueTest.java
+++ b/src/test/java/com/android/tools/r8/apimodel/ClassValueTest.java
@@ -17,8 +17,8 @@
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/apimodel/JavaSourceCodePrinter.java b/src/test/java/com/android/tools/r8/apimodel/JavaSourceCodePrinter.java
index 2618fd4..5a867f6 100644
--- a/src/test/java/com/android/tools/r8/apimodel/JavaSourceCodePrinter.java
+++ b/src/test/java/com/android/tools/r8/apimodel/JavaSourceCodePrinter.java
@@ -5,8 +5,8 @@
 package com.android.tools.r8.apimodel;
 
 import com.android.tools.r8.utils.internal.Action;
-import com.android.tools.r8.utils.StringUtils;
-import com.android.tools.r8.utils.StringUtils.BraceType;
+import com.android.tools.r8.utils.internal.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils.BraceType;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.HashSet;
diff --git a/src/test/java/com/android/tools/r8/assistant/GenerateAssistantRuntimeMethods.java b/src/test/java/com/android/tools/r8/assistant/GenerateAssistantRuntimeMethods.java
index 13b9828..0fba73d 100644
--- a/src/test/java/com/android/tools/r8/assistant/GenerateAssistantRuntimeMethods.java
+++ b/src/test/java/com/android/tools/r8/assistant/GenerateAssistantRuntimeMethods.java
@@ -17,7 +17,7 @@
 import com.android.tools.r8.cfmethodgeneration.MethodGenerationBase;
 import com.android.tools.r8.graph.DexEncodedMethod;
 import com.android.tools.r8.graph.DexType;
-import com.android.tools.r8.utils.FileUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.ArrayList;
 import java.util.Comparator;
diff --git a/src/test/java/com/android/tools/r8/benchmarks/BenchmarkCollectionPrinter.java b/src/test/java/com/android/tools/r8/benchmarks/BenchmarkCollectionPrinter.java
index b9b5ed0..9162544 100644
--- a/src/test/java/com/android/tools/r8/benchmarks/BenchmarkCollectionPrinter.java
+++ b/src/test/java/com/android/tools/r8/benchmarks/BenchmarkCollectionPrinter.java
@@ -7,9 +7,9 @@
 import com.android.tools.r8.ToolHelper.ProcessResult;
 import com.android.tools.r8.utils.CollectionUtils;
 import com.android.tools.r8.utils.ListUtils;
-import com.android.tools.r8.utils.StringUtils;
-import com.android.tools.r8.utils.StringUtils.BraceType;
 import com.android.tools.r8.utils.internal.IterableUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils.BraceType;
 import com.google.common.base.Strings;
 import com.google.common.collect.Sets;
 import com.google.common.hash.Hasher;
diff --git a/src/test/java/com/android/tools/r8/benchmarks/appdumps/AppDumpBenchmarkBuilder.java b/src/test/java/com/android/tools/r8/benchmarks/appdumps/AppDumpBenchmarkBuilder.java
index 8a1271b..b43d562 100644
--- a/src/test/java/com/android/tools/r8/benchmarks/appdumps/AppDumpBenchmarkBuilder.java
+++ b/src/test/java/com/android/tools/r8/benchmarks/appdumps/AppDumpBenchmarkBuilder.java
@@ -31,8 +31,8 @@
 import com.android.tools.r8.keepanno.annotations.KeepEdge;
 import com.android.tools.r8.keepanno.annotations.KeepItemKind;
 import com.android.tools.r8.keepanno.annotations.KeepTarget;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableSet;
 import java.io.IOException;
 import java.lang.annotation.RetentionPolicy;
diff --git a/src/test/java/com/android/tools/r8/benchmarks/appdumps/PackageSplitResources.java b/src/test/java/com/android/tools/r8/benchmarks/appdumps/PackageSplitResources.java
index d6dc468..bb60137 100644
--- a/src/test/java/com/android/tools/r8/benchmarks/appdumps/PackageSplitResources.java
+++ b/src/test/java/com/android/tools/r8/benchmarks/appdumps/PackageSplitResources.java
@@ -3,9 +3,9 @@
 // BSD-style license that can be found in the LICENSE file.
 package com.android.tools.r8.benchmarks.appdumps;
 
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.ListUtils;
 import com.android.tools.r8.utils.ZipUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import java.io.File;
 import java.io.IOException;
 import java.nio.file.Files;
diff --git a/src/test/java/com/android/tools/r8/benchmarks/retrace/RetraceStackTraceBenchmark.java b/src/test/java/com/android/tools/r8/benchmarks/retrace/RetraceStackTraceBenchmark.java
index bbcfb5d..1be66d4 100644
--- a/src/test/java/com/android/tools/r8/benchmarks/retrace/RetraceStackTraceBenchmark.java
+++ b/src/test/java/com/android/tools/r8/benchmarks/retrace/RetraceStackTraceBenchmark.java
@@ -22,7 +22,7 @@
 import com.android.tools.r8.retrace.ProguardMappingSupplier;
 import com.android.tools.r8.retrace.Retrace;
 import com.android.tools.r8.retrace.RetraceCommand;
-import com.android.tools.r8.utils.FileUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.nio.file.Files;
diff --git a/src/test/java/com/android/tools/r8/blastradius/GenerateBlastRadiusHtmlReportTemplate.java b/src/test/java/com/android/tools/r8/blastradius/GenerateBlastRadiusHtmlReportTemplate.java
index c44cc2f..2657b4a 100644
--- a/src/test/java/com/android/tools/r8/blastradius/GenerateBlastRadiusHtmlReportTemplate.java
+++ b/src/test/java/com/android/tools/r8/blastradius/GenerateBlastRadiusHtmlReportTemplate.java
@@ -11,8 +11,8 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.cfmethodgeneration.MethodGenerationBase;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/bridgeremoval/ProtectedBridgeRemovalTest.java b/src/test/java/com/android/tools/r8/bridgeremoval/ProtectedBridgeRemovalTest.java
index 6747779..20c7bac 100644
--- a/src/test/java/com/android/tools/r8/bridgeremoval/ProtectedBridgeRemovalTest.java
+++ b/src/test/java/com/android/tools/r8/bridgeremoval/ProtectedBridgeRemovalTest.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.BeforeClass;
diff --git a/src/test/java/com/android/tools/r8/bridgeremoval/hoisting/BridgeAfterAssumeNoSideEffectsTest.java b/src/test/java/com/android/tools/r8/bridgeremoval/hoisting/BridgeAfterAssumeNoSideEffectsTest.java
index 4fb933d..58acc5f 100644
--- a/src/test/java/com/android/tools/r8/bridgeremoval/hoisting/BridgeAfterAssumeNoSideEffectsTest.java
+++ b/src/test/java/com/android/tools/r8/bridgeremoval/hoisting/BridgeAfterAssumeNoSideEffectsTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/cf/ClassFileVersion67Test.java b/src/test/java/com/android/tools/r8/cf/ClassFileVersion67Test.java
index 5b77394..6a279a5 100644
--- a/src/test/java/com/android/tools/r8/cf/ClassFileVersion67Test.java
+++ b/src/test/java/com/android/tools/r8/cf/ClassFileVersion67Test.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/cf/ClassFileVersion68Test.java b/src/test/java/com/android/tools/r8/cf/ClassFileVersion68Test.java
index 4fc2adc..da8ed26 100644
--- a/src/test/java/com/android/tools/r8/cf/ClassFileVersion68Test.java
+++ b/src/test/java/com/android/tools/r8/cf/ClassFileVersion68Test.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/cf/ClassFileVersion69Test.java b/src/test/java/com/android/tools/r8/cf/ClassFileVersion69Test.java
index 9d9099c..bae2660 100644
--- a/src/test/java/com/android/tools/r8/cf/ClassFileVersion69Test.java
+++ b/src/test/java/com/android/tools/r8/cf/ClassFileVersion69Test.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/cf/ClassFileVersion70Test.java b/src/test/java/com/android/tools/r8/cf/ClassFileVersion70Test.java
index 87560f4..df09100 100644
--- a/src/test/java/com/android/tools/r8/cf/ClassFileVersion70Test.java
+++ b/src/test/java/com/android/tools/r8/cf/ClassFileVersion70Test.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/cf/ClassFileVersion71Test.java b/src/test/java/com/android/tools/r8/cf/ClassFileVersion71Test.java
index b026aa8..b17fa84 100644
--- a/src/test/java/com/android/tools/r8/cf/ClassFileVersion71Test.java
+++ b/src/test/java/com/android/tools/r8/cf/ClassFileVersion71Test.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/cf/CompanionClassPreamblePositionTest.java b/src/test/java/com/android/tools/r8/cf/CompanionClassPreamblePositionTest.java
index 90fd31b..16ed150 100644
--- a/src/test/java/com/android/tools/r8/cf/CompanionClassPreamblePositionTest.java
+++ b/src/test/java/com/android/tools/r8/cf/CompanionClassPreamblePositionTest.java
@@ -13,10 +13,10 @@
 import com.android.tools.r8.transformers.ClassFileTransformer.LineTranslation;
 import com.android.tools.r8.transformers.MethodTransformer.MethodContext;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import it.unimi.dsi.fastutil.ints.Int2IntMap;
 import it.unimi.dsi.fastutil.ints.Int2IntOpenHashMap;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/cf/GetClassLdcClassTest.java b/src/test/java/com/android/tools/r8/cf/GetClassLdcClassTest.java
index 82d2be9..09c443b 100644
--- a/src/test/java/com/android/tools/r8/cf/GetClassLdcClassTest.java
+++ b/src/test/java/com/android/tools/r8/cf/GetClassLdcClassTest.java
@@ -11,8 +11,8 @@
 import com.android.tools.r8.R8TestRunResult;
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/cf/KeepDeserializeLambdaMethodTestRunner.java b/src/test/java/com/android/tools/r8/cf/KeepDeserializeLambdaMethodTestRunner.java
index 6716f80..07caee6 100644
--- a/src/test/java/com/android/tools/r8/cf/KeepDeserializeLambdaMethodTestRunner.java
+++ b/src/test/java/com/android/tools/r8/cf/KeepDeserializeLambdaMethodTestRunner.java
@@ -11,9 +11,9 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/cf/LeadingZeroPositionTest.java b/src/test/java/com/android/tools/r8/cf/LeadingZeroPositionTest.java
index 28dc97e..8058ef5 100644
--- a/src/test/java/com/android/tools/r8/cf/LeadingZeroPositionTest.java
+++ b/src/test/java/com/android/tools/r8/cf/LeadingZeroPositionTest.java
@@ -10,9 +10,9 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.transformers.ClassFileTransformer.MethodPredicate;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Assume;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/cf/MissingClassJoinsToObjectTest.java b/src/test/java/com/android/tools/r8/cf/MissingClassJoinsToObjectTest.java
index eb27756..9b06cc0 100644
--- a/src/test/java/com/android/tools/r8/cf/MissingClassJoinsToObjectTest.java
+++ b/src/test/java/com/android/tools/r8/cf/MissingClassJoinsToObjectTest.java
@@ -15,8 +15,8 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ToolHelper;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.UnverifiableCfCodeDiagnostic;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/cf/MultipleZeroPositionsTest.java b/src/test/java/com/android/tools/r8/cf/MultipleZeroPositionsTest.java
index d32a594..c1d074d 100644
--- a/src/test/java/com/android/tools/r8/cf/MultipleZeroPositionsTest.java
+++ b/src/test/java/com/android/tools/r8/cf/MultipleZeroPositionsTest.java
@@ -11,9 +11,9 @@
 import com.android.tools.r8.transformers.ClassFileTransformer.LineTranslation;
 import com.android.tools.r8.transformers.MethodTransformer.MethodContext;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import it.unimi.dsi.fastutil.ints.Int2IntMap;
 import it.unimi.dsi.fastutil.ints.Int2IntOpenHashMap;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/cf/PrintSeedsWithDeserializeLambdaMethodTest.java b/src/test/java/com/android/tools/r8/cf/PrintSeedsWithDeserializeLambdaMethodTest.java
index 89f13b9..d17a1be 100644
--- a/src/test/java/com/android/tools/r8/cf/PrintSeedsWithDeserializeLambdaMethodTest.java
+++ b/src/test/java/com/android/tools/r8/cf/PrintSeedsWithDeserializeLambdaMethodTest.java
@@ -9,9 +9,9 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/cf/SillyBlockOrderTest.java b/src/test/java/com/android/tools/r8/cf/SillyBlockOrderTest.java
index dc74aef..10e896c 100644
--- a/src/test/java/com/android/tools/r8/cf/SillyBlockOrderTest.java
+++ b/src/test/java/com/android/tools/r8/cf/SillyBlockOrderTest.java
@@ -8,10 +8,10 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/cf/TryRangeTestRunner.java b/src/test/java/com/android/tools/r8/cf/TryRangeTestRunner.java
index bf227c8..baf6523 100644
--- a/src/test/java/com/android/tools/r8/cf/TryRangeTestRunner.java
+++ b/src/test/java/com/android/tools/r8/cf/TryRangeTestRunner.java
@@ -22,9 +22,9 @@
 import com.android.tools.r8.ir.code.IRCode;
 import com.android.tools.r8.ir.code.Instruction;
 import com.android.tools.r8.ir.code.InstructionListIterator;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/cf/bootstrap/BootstrapTest.java b/src/test/java/com/android/tools/r8/cf/bootstrap/BootstrapTest.java
index c381b0d..89b4fe6 100644
--- a/src/test/java/com/android/tools/r8/cf/bootstrap/BootstrapTest.java
+++ b/src/test/java/com/android/tools/r8/cf/bootstrap/BootstrapTest.java
@@ -12,8 +12,8 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.ToolHelper.ProcessResult;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.base.Charsets;
 import java.nio.file.Path;
 import java.nio.file.Paths;
diff --git a/src/test/java/com/android/tools/r8/cf/frames/InitBeforeNewInInstructionStreamTest.java b/src/test/java/com/android/tools/r8/cf/frames/InitBeforeNewInInstructionStreamTest.java
index c0808d2..ac4cc05 100644
--- a/src/test/java/com/android/tools/r8/cf/frames/InitBeforeNewInInstructionStreamTest.java
+++ b/src/test/java/com/android/tools/r8/cf/frames/InitBeforeNewInInstructionStreamTest.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import javassist.ByteArrayClassPath;
 import javassist.ClassPool;
 import javassist.CtClass;
diff --git a/src/test/java/com/android/tools/r8/cf/methodhandles/InvalidBootstrapMethodHandleTest.java b/src/test/java/com/android/tools/r8/cf/methodhandles/InvalidBootstrapMethodHandleTest.java
index a815910..232f255 100644
--- a/src/test/java/com/android/tools/r8/cf/methodhandles/InvalidBootstrapMethodHandleTest.java
+++ b/src/test/java/com/android/tools/r8/cf/methodhandles/InvalidBootstrapMethodHandleTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestRunResult;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableMap;
 import java.util.List;
 import java.util.Map;
diff --git a/src/test/java/com/android/tools/r8/cf/methodhandles/InvokeMethodHandleRuntimeErrorTest.java b/src/test/java/com/android/tools/r8/cf/methodhandles/InvokeMethodHandleRuntimeErrorTest.java
index 622f02c..e756775 100644
--- a/src/test/java/com/android/tools/r8/cf/methodhandles/InvokeMethodHandleRuntimeErrorTest.java
+++ b/src/test/java/com/android/tools/r8/cf/methodhandles/InvokeMethodHandleRuntimeErrorTest.java
@@ -15,7 +15,7 @@
 import com.android.tools.r8.errors.UnsupportedFeatureDiagnostic;
 import com.android.tools.r8.references.ClassReference;
 import com.android.tools.r8.references.MethodReference;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.lang.invoke.MethodHandle;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/cf/methodhandles/InvokePolymorphicTypesTest.java b/src/test/java/com/android/tools/r8/cf/methodhandles/InvokePolymorphicTypesTest.java
index f1b4516..7896b94 100644
--- a/src/test/java/com/android/tools/r8/cf/methodhandles/InvokePolymorphicTypesTest.java
+++ b/src/test/java/com/android/tools/r8/cf/methodhandles/InvokePolymorphicTypesTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ToolHelper.DexVm.Version;
 import com.android.tools.r8.references.Reference;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.lang.invoke.MethodHandle;
 import java.lang.invoke.MethodHandles;
 import java.lang.invoke.MethodType;
diff --git a/src/test/java/com/android/tools/r8/cf/methodhandles/MethodHandleTestRunner.java b/src/test/java/com/android/tools/r8/cf/methodhandles/MethodHandleTestRunner.java
index b513d1b..95ead52 100644
--- a/src/test/java/com/android/tools/r8/cf/methodhandles/MethodHandleTestRunner.java
+++ b/src/test/java/com/android/tools/r8/cf/methodhandles/MethodHandleTestRunner.java
@@ -21,7 +21,7 @@
 import com.android.tools.r8.cf.methodhandles.MethodHandleTest.I;
 import com.android.tools.r8.cf.methodhandles.MethodHandleTest.Impl;
 import com.android.tools.r8.errors.UnsupportedFeatureDiagnostic;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableList.Builder;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/cf/methodhandles/fields/ClassFieldMethodHandleTest.java b/src/test/java/com/android/tools/r8/cf/methodhandles/fields/ClassFieldMethodHandleTest.java
index 9dc5739..abec6ab 100644
--- a/src/test/java/com/android/tools/r8/cf/methodhandles/fields/ClassFieldMethodHandleTest.java
+++ b/src/test/java/com/android/tools/r8/cf/methodhandles/fields/ClassFieldMethodHandleTest.java
@@ -19,7 +19,7 @@
 import com.android.tools.r8.errors.UnsupportedFeatureDiagnostic;
 import com.android.tools.r8.transformers.ClassTransformer;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableMap;
 import java.lang.invoke.MethodHandle;
 import java.lang.invoke.MethodHandles;
diff --git a/src/test/java/com/android/tools/r8/cf/methodhandles/fields/InterfaceFieldMethodHandleTest.java b/src/test/java/com/android/tools/r8/cf/methodhandles/fields/InterfaceFieldMethodHandleTest.java
index 6c435c0..b0efddf 100644
--- a/src/test/java/com/android/tools/r8/cf/methodhandles/fields/InterfaceFieldMethodHandleTest.java
+++ b/src/test/java/com/android/tools/r8/cf/methodhandles/fields/InterfaceFieldMethodHandleTest.java
@@ -17,7 +17,7 @@
 import com.android.tools.r8.ToolHelper.DexVm.Version;
 import com.android.tools.r8.errors.UnsupportedFeatureDiagnostic;
 import com.android.tools.r8.transformers.ClassTransformer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.lang.invoke.MethodHandle;
 import java.lang.invoke.MethodHandles;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/cf/methodhandles/invokespecial/InvokeSpecialMethodHandleTest.java b/src/test/java/com/android/tools/r8/cf/methodhandles/invokespecial/InvokeSpecialMethodHandleTest.java
index a3fba21..c5e7bc0 100644
--- a/src/test/java/com/android/tools/r8/cf/methodhandles/invokespecial/InvokeSpecialMethodHandleTest.java
+++ b/src/test/java/com/android/tools/r8/cf/methodhandles/invokespecial/InvokeSpecialMethodHandleTest.java
@@ -17,7 +17,7 @@
 import com.android.tools.r8.apimodel.ApiModelingTestHelper;
 import com.android.tools.r8.errors.UnsupportedFeatureDiagnostic;
 import com.android.tools.r8.transformers.ClassTransformer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.lang.invoke.MethodHandle;
 import java.lang.invoke.MethodHandles;
 import java.lang.invoke.MethodType;
diff --git a/src/test/java/com/android/tools/r8/cf/stackmap/UndefinedTypesAssignmentTest.java b/src/test/java/com/android/tools/r8/cf/stackmap/UndefinedTypesAssignmentTest.java
index 09de4a6..0f7e73e 100644
--- a/src/test/java/com/android/tools/r8/cf/stackmap/UndefinedTypesAssignmentTest.java
+++ b/src/test/java/com/android/tools/r8/cf/stackmap/UndefinedTypesAssignmentTest.java
@@ -9,8 +9,8 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.UnverifiableCfCodeDiagnostic;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/cfmethodgeneration/CfClassGenerator.java b/src/test/java/com/android/tools/r8/cfmethodgeneration/CfClassGenerator.java
index e6b8bf4..b86ff67 100644
--- a/src/test/java/com/android/tools/r8/cfmethodgeneration/CfClassGenerator.java
+++ b/src/test/java/com/android/tools/r8/cfmethodgeneration/CfClassGenerator.java
@@ -15,11 +15,11 @@
 import com.android.tools.r8.graph.JarClassFileReader;
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.references.MethodReference;
-import com.android.tools.r8.utils.internal.Box;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.InternalOptions;
 import com.android.tools.r8.utils.Reporter;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.Box;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.util.HashMap;
 import java.util.Iterator;
diff --git a/src/test/java/com/android/tools/r8/cfmethodgeneration/CodeGenerationBase.java b/src/test/java/com/android/tools/r8/cfmethodgeneration/CodeGenerationBase.java
index ddaa213..01e778a 100644
--- a/src/test/java/com/android/tools/r8/cfmethodgeneration/CodeGenerationBase.java
+++ b/src/test/java/com/android/tools/r8/cfmethodgeneration/CodeGenerationBase.java
@@ -9,8 +9,8 @@
 import com.android.tools.r8.ToolHelper.ProcessResult;
 import com.android.tools.r8.graph.DexItemFactory;
 import com.android.tools.r8.graph.DexType;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.File;
 import java.io.IOException;
diff --git a/src/test/java/com/android/tools/r8/cfmethodgeneration/GenerateTypeSwitchMethods.java b/src/test/java/com/android/tools/r8/cfmethodgeneration/GenerateTypeSwitchMethods.java
index 82e6888..7feafab 100644
--- a/src/test/java/com/android/tools/r8/cfmethodgeneration/GenerateTypeSwitchMethods.java
+++ b/src/test/java/com/android/tools/r8/cfmethodgeneration/GenerateTypeSwitchMethods.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ToolHelper.TestDataSourceSet;
 import com.android.tools.r8.graph.DexType;
-import com.android.tools.r8.utils.FileUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.charset.StandardCharsets;
 import java.util.ArrayList;
diff --git a/src/test/java/com/android/tools/r8/cfmethodgeneration/MethodGenerationBase.java b/src/test/java/com/android/tools/r8/cfmethodgeneration/MethodGenerationBase.java
index 7db39d3..6f0e70f 100644
--- a/src/test/java/com/android/tools/r8/cfmethodgeneration/MethodGenerationBase.java
+++ b/src/test/java/com/android/tools/r8/cfmethodgeneration/MethodGenerationBase.java
@@ -19,11 +19,11 @@
 import com.android.tools.r8.graph.JarClassFileReader;
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.references.Reference;
-import com.android.tools.r8.utils.internal.BooleanBox;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.InternalOptions;
 import com.android.tools.r8.utils.ListUtils;
 import com.android.tools.r8.utils.Reporter;
+import com.android.tools.r8.utils.internal.BooleanBox;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Sets;
 import java.io.ByteArrayOutputStream;
diff --git a/src/test/java/com/android/tools/r8/checkdiscarded/CheckAllMembersDiscardedTest.java b/src/test/java/com/android/tools/r8/checkdiscarded/CheckAllMembersDiscardedTest.java
index 9956f19..3950250 100644
--- a/src/test/java/com/android/tools/r8/checkdiscarded/CheckAllMembersDiscardedTest.java
+++ b/src/test/java/com/android/tools/r8/checkdiscarded/CheckAllMembersDiscardedTest.java
@@ -9,9 +9,9 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.errors.CheckDiscardDiagnostic;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.AssertUtils;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/checkdiscarded/CheckSingleMemberDiscardedTest.java b/src/test/java/com/android/tools/r8/checkdiscarded/CheckSingleMemberDiscardedTest.java
index 972eee1..2a89e21 100644
--- a/src/test/java/com/android/tools/r8/checkdiscarded/CheckSingleMemberDiscardedTest.java
+++ b/src/test/java/com/android/tools/r8/checkdiscarded/CheckSingleMemberDiscardedTest.java
@@ -7,9 +7,9 @@
 import com.android.tools.r8.NeverInline;
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.AssertUtils;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/classmerging/horizontal/ServiceLoaderParentTest.java b/src/test/java/com/android/tools/r8/classmerging/horizontal/ServiceLoaderParentTest.java
index cf3fe25..1ce5665 100644
--- a/src/test/java/com/android/tools/r8/classmerging/horizontal/ServiceLoaderParentTest.java
+++ b/src/test/java/com/android/tools/r8/classmerging/horizontal/ServiceLoaderParentTest.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.NoVerticalClassMerging;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.origin.Origin;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.Lists;
 import java.util.List;
 import java.util.ServiceLoader;
diff --git a/src/test/java/com/android/tools/r8/classmerging/horizontal/ServiceLoaderTest.java b/src/test/java/com/android/tools/r8/classmerging/horizontal/ServiceLoaderTest.java
index c457680..d61686a 100644
--- a/src/test/java/com/android/tools/r8/classmerging/horizontal/ServiceLoaderTest.java
+++ b/src/test/java/com/android/tools/r8/classmerging/horizontal/ServiceLoaderTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.DataEntryResource;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.origin.Origin;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.Lists;
 import java.util.List;
 import java.util.ServiceLoader;
diff --git a/src/test/java/com/android/tools/r8/classmerging/horizontal/interfaces/CollisionWithDefaultMethodsTest.java b/src/test/java/com/android/tools/r8/classmerging/horizontal/interfaces/CollisionWithDefaultMethodsTest.java
index a0af340..7b182e6 100644
--- a/src/test/java/com/android/tools/r8/classmerging/horizontal/interfaces/CollisionWithDefaultMethodsTest.java
+++ b/src/test/java/com/android/tools/r8/classmerging/horizontal/interfaces/CollisionWithDefaultMethodsTest.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/classmerging/horizontalstatic/InliningAfterStaticClassMergerTest.java b/src/test/java/com/android/tools/r8/classmerging/horizontalstatic/InliningAfterStaticClassMergerTest.java
index 00ab767..4486078 100644
--- a/src/test/java/com/android/tools/r8/classmerging/horizontalstatic/InliningAfterStaticClassMergerTest.java
+++ b/src/test/java/com/android/tools/r8/classmerging/horizontalstatic/InliningAfterStaticClassMergerTest.java
@@ -12,10 +12,10 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FoundClassSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import java.util.stream.Collectors;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/classmerging/horizontalstatic/StaticClassMergerInterfaceTest.java b/src/test/java/com/android/tools/r8/classmerging/horizontalstatic/StaticClassMergerInterfaceTest.java
index e5520bd..512ff5c 100644
--- a/src/test/java/com/android/tools/r8/classmerging/horizontalstatic/StaticClassMergerInterfaceTest.java
+++ b/src/test/java/com/android/tools/r8/classmerging/horizontalstatic/StaticClassMergerInterfaceTest.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/classmerging/horizontalstatic/StaticClassMergerTest.java b/src/test/java/com/android/tools/r8/classmerging/horizontalstatic/StaticClassMergerTest.java
index dd1000d..0f110c8 100644
--- a/src/test/java/com/android/tools/r8/classmerging/horizontalstatic/StaticClassMergerTest.java
+++ b/src/test/java/com/android/tools/r8/classmerging/horizontalstatic/StaticClassMergerTest.java
@@ -11,8 +11,8 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.FoundClassSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.util.List;
 import java.util.concurrent.ExecutionException;
diff --git a/src/test/java/com/android/tools/r8/classmerging/vertical/ForceInliningWithStaticInterfaceMethodTest.java b/src/test/java/com/android/tools/r8/classmerging/vertical/ForceInliningWithStaticInterfaceMethodTest.java
index ff5d1a8..b628b2a 100644
--- a/src/test/java/com/android/tools/r8/classmerging/vertical/ForceInliningWithStaticInterfaceMethodTest.java
+++ b/src/test/java/com/android/tools/r8/classmerging/vertical/ForceInliningWithStaticInterfaceMethodTest.java
@@ -6,7 +6,7 @@
 
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 
 /** Regression test for b/120121170. */
diff --git a/src/test/java/com/android/tools/r8/classmerging/vertical/InterfaceWithGetProxyClassTest.java b/src/test/java/com/android/tools/r8/classmerging/vertical/InterfaceWithGetProxyClassTest.java
index 93e146c..165c010 100644
--- a/src/test/java/com/android/tools/r8/classmerging/vertical/InterfaceWithGetProxyClassTest.java
+++ b/src/test/java/com/android/tools/r8/classmerging/vertical/InterfaceWithGetProxyClassTest.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.lang.reflect.InvocationHandler;
 import java.lang.reflect.Proxy;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/classmerging/vertical/InterfaceWithNewProxyInstanceTest.java b/src/test/java/com/android/tools/r8/classmerging/vertical/InterfaceWithNewProxyInstanceTest.java
index a512441..ab8a6d3 100644
--- a/src/test/java/com/android/tools/r8/classmerging/vertical/InterfaceWithNewProxyInstanceTest.java
+++ b/src/test/java/com/android/tools/r8/classmerging/vertical/InterfaceWithNewProxyInstanceTest.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.lang.reflect.Proxy;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/classmerging/vertical/StaticInitializerTest.java b/src/test/java/com/android/tools/r8/classmerging/vertical/StaticInitializerTest.java
index 637ec96..9057049 100644
--- a/src/test/java/com/android/tools/r8/classmerging/vertical/StaticInitializerTest.java
+++ b/src/test/java/com/android/tools/r8/classmerging/vertical/StaticInitializerTest.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/classmerging/vertical/VerticalClassMergerTest.java b/src/test/java/com/android/tools/r8/classmerging/vertical/VerticalClassMergerTest.java
index 627c16f..4526f4b 100644
--- a/src/test/java/com/android/tools/r8/classmerging/vertical/VerticalClassMergerTest.java
+++ b/src/test/java/com/android/tools/r8/classmerging/vertical/VerticalClassMergerTest.java
@@ -33,15 +33,15 @@
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.AndroidApp;
 import com.android.tools.r8.utils.AndroidApp.Builder;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.InternalOptions;
 import com.android.tools.r8.utils.InternalOptions.InlinerOptions;
 import com.android.tools.r8.utils.SetUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FoundClassSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 import java.io.File;
diff --git a/src/test/java/com/android/tools/r8/code/invokedynamic/InvokeCustomRuntimeErrorTest.java b/src/test/java/com/android/tools/r8/code/invokedynamic/InvokeCustomRuntimeErrorTest.java
index 9f6a935..2d60701 100644
--- a/src/test/java/com/android/tools/r8/code/invokedynamic/InvokeCustomRuntimeErrorTest.java
+++ b/src/test/java/com/android/tools/r8/code/invokedynamic/InvokeCustomRuntimeErrorTest.java
@@ -16,7 +16,7 @@
 import com.android.tools.r8.references.MethodReference;
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.lang.invoke.CallSite;
 import java.lang.invoke.ConstantCallSite;
 import java.lang.invoke.MethodHandle;
diff --git a/src/test/java/com/android/tools/r8/code/invokedynamic/InvokeDynamicVirtualDispatchToDefaultInterfaceMethodTest.java b/src/test/java/com/android/tools/r8/code/invokedynamic/InvokeDynamicVirtualDispatchToDefaultInterfaceMethodTest.java
index 3b592bd..04e258e 100644
--- a/src/test/java/com/android/tools/r8/code/invokedynamic/InvokeDynamicVirtualDispatchToDefaultInterfaceMethodTest.java
+++ b/src/test/java/com/android/tools/r8/code/invokedynamic/InvokeDynamicVirtualDispatchToDefaultInterfaceMethodTest.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.references.ClassReference;
 import com.android.tools.r8.references.MethodReference;
 import com.android.tools.r8.references.Reference;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.lang.invoke.CallSite;
 import java.lang.invoke.ConstantCallSite;
 import java.lang.invoke.MethodHandle;
diff --git a/src/test/java/com/android/tools/r8/compatproguard/CompatKeepClassMemberNamesTestRunner.java b/src/test/java/com/android/tools/r8/compatproguard/CompatKeepClassMemberNamesTestRunner.java
index bb999d8..fe076e5 100644
--- a/src/test/java/com/android/tools/r8/compatproguard/CompatKeepClassMemberNamesTestRunner.java
+++ b/src/test/java/com/android/tools/r8/compatproguard/CompatKeepClassMemberNamesTestRunner.java
@@ -19,11 +19,11 @@
 import com.android.tools.r8.TestRunResult;
 import com.android.tools.r8.TestShrinkerBuilder;
 import com.android.tools.r8.compatproguard.CompatKeepClassMemberNamesTest.Bar;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FieldSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.Collection;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/compatproguard/ShrinkFieldsWhileKeepingFieldNameTest.java b/src/test/java/com/android/tools/r8/compatproguard/ShrinkFieldsWhileKeepingFieldNameTest.java
index dd4ee99..220fac1 100644
--- a/src/test/java/com/android/tools/r8/compatproguard/ShrinkFieldsWhileKeepingFieldNameTest.java
+++ b/src/test/java/com/android/tools/r8/compatproguard/ShrinkFieldsWhileKeepingFieldNameTest.java
@@ -10,9 +10,9 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Objects;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/compatproguard/ifrules/ConditionalOnInlinedFieldTest.java b/src/test/java/com/android/tools/r8/compatproguard/ifrules/ConditionalOnInlinedFieldTest.java
index 35c008c..3341c6e 100644
--- a/src/test/java/com/android/tools/r8/compatproguard/ifrules/ConditionalOnInlinedFieldTest.java
+++ b/src/test/java/com/android/tools/r8/compatproguard/ifrules/ConditionalOnInlinedFieldTest.java
@@ -11,9 +11,9 @@
 import com.android.tools.r8.TestRunResult;
 import com.android.tools.r8.TestShrinkerBuilder;
 import com.android.tools.r8.shaking.methods.MethodsTestBase.Shrinker;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.internal.ArrayUtils;
 import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import java.util.Optional;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/compatproguard/ifrules/ConditionalOnInlinedTest.java b/src/test/java/com/android/tools/r8/compatproguard/ifrules/ConditionalOnInlinedTest.java
index faf8537..fbd951a 100644
--- a/src/test/java/com/android/tools/r8/compatproguard/ifrules/ConditionalOnInlinedTest.java
+++ b/src/test/java/com/android/tools/r8/compatproguard/ifrules/ConditionalOnInlinedTest.java
@@ -11,8 +11,8 @@
 import com.android.tools.r8.TestRunResult;
 import com.android.tools.r8.TestShrinkerBuilder;
 import com.android.tools.r8.shaking.methods.MethodsTestBase.Shrinker;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.internal.ArrayUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.Collection;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/compilerapi/BinaryCompatibilityTestCollection.java b/src/test/java/com/android/tools/r8/compilerapi/BinaryCompatibilityTestCollection.java
index 103b419..e841fd3 100644
--- a/src/test/java/com/android/tools/r8/compilerapi/BinaryCompatibilityTestCollection.java
+++ b/src/test/java/com/android/tools/r8/compilerapi/BinaryCompatibilityTestCollection.java
@@ -18,10 +18,10 @@
 import com.android.tools.r8.transformers.ClassFileTransformer;
 import com.android.tools.r8.transformers.ClassFileTransformer.InnerClassPredicate;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.internal.IntBox;
 import com.android.tools.r8.utils.ZipUtils;
 import com.android.tools.r8.utils.ZipUtils.ZipBuilder;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.IntBox;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Sets;
diff --git a/src/test/java/com/android/tools/r8/compilerapi/maindex/MainDexListTest.java b/src/test/java/com/android/tools/r8/compilerapi/maindex/MainDexListTest.java
index 47430fd..5e8adf6 100644
--- a/src/test/java/com/android/tools/r8/compilerapi/maindex/MainDexListTest.java
+++ b/src/test/java/com/android/tools/r8/compilerapi/maindex/MainDexListTest.java
@@ -19,7 +19,7 @@
 import com.android.tools.r8.compilerapi.CompilerApiTest;
 import com.android.tools.r8.compilerapi.CompilerApiTestRunner;
 import com.android.tools.r8.errors.UnsupportedMainDexListUsageDiagnostic;
-import com.android.tools.r8.utils.FileUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import java.nio.file.Path;
 import java.util.Collections;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/compilerapi/maindex/MainDexRulesTest.java b/src/test/java/com/android/tools/r8/compilerapi/maindex/MainDexRulesTest.java
index 5701058..70d35c2 100644
--- a/src/test/java/com/android/tools/r8/compilerapi/maindex/MainDexRulesTest.java
+++ b/src/test/java/com/android/tools/r8/compilerapi/maindex/MainDexRulesTest.java
@@ -16,7 +16,7 @@
 import com.android.tools.r8.compilerapi.CompilerApiTest;
 import com.android.tools.r8.compilerapi.CompilerApiTestRunner;
 import com.android.tools.r8.origin.PathOrigin;
-import com.android.tools.r8.utils.FileUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/d8/DuplicateAnnotationTest.java b/src/test/java/com/android/tools/r8/d8/DuplicateAnnotationTest.java
index 3214f80..5262faa 100644
--- a/src/test/java/com/android/tools/r8/d8/DuplicateAnnotationTest.java
+++ b/src/test/java/com/android/tools/r8/d8/DuplicateAnnotationTest.java
@@ -14,12 +14,12 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ToolHelper;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.AnnotationSubject;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FieldSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
diff --git a/src/test/java/com/android/tools/r8/d8/IntermediateModeMarkerTest.java b/src/test/java/com/android/tools/r8/d8/IntermediateModeMarkerTest.java
index ab92812..5a3ebb5 100644
--- a/src/test/java/com/android/tools/r8/d8/IntermediateModeMarkerTest.java
+++ b/src/test/java/com/android/tools/r8/d8/IntermediateModeMarkerTest.java
@@ -23,7 +23,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.dex.Marker;
 import com.android.tools.r8.origin.Origin;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Collection;
 import java.util.HashMap;
 import java.util.Map;
diff --git a/src/test/java/com/android/tools/r8/d8/ProguardMapSortByTest.java b/src/test/java/com/android/tools/r8/d8/ProguardMapSortByTest.java
index 35b0e0f..ef5e9c2 100644
--- a/src/test/java/com/android/tools/r8/d8/ProguardMapSortByTest.java
+++ b/src/test/java/com/android/tools/r8/d8/ProguardMapSortByTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.FileUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Files;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/d8/ThrowingConstStringTest.java b/src/test/java/com/android/tools/r8/d8/ThrowingConstStringTest.java
index 9ae8bb3..412c0ab 100644
--- a/src/test/java/com/android/tools/r8/d8/ThrowingConstStringTest.java
+++ b/src/test/java/com/android/tools/r8/d8/ThrowingConstStringTest.java
@@ -8,9 +8,9 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/dagger/DaggerBasicTestBase.java b/src/test/java/com/android/tools/r8/dagger/DaggerBasicTestBase.java
index 81d71f5..8ac3576 100644
--- a/src/test/java/com/android/tools/r8/dagger/DaggerBasicTestBase.java
+++ b/src/test/java/com/android/tools/r8/dagger/DaggerBasicTestBase.java
@@ -11,8 +11,8 @@
 import com.android.tools.r8.transformers.ClassTransformer;
 import com.android.tools.r8.transformers.MethodTransformer;
 import com.android.tools.r8.utils.DaggerUtils;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.ZipUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.ImmutableSet;
diff --git a/src/test/java/com/android/tools/r8/deadcode/DifferentAssumptionsOnReturnValuesTest.java b/src/test/java/com/android/tools/r8/deadcode/DifferentAssumptionsOnReturnValuesTest.java
index 0b457b8..d017386 100644
--- a/src/test/java/com/android/tools/r8/deadcode/DifferentAssumptionsOnReturnValuesTest.java
+++ b/src/test/java/com/android/tools/r8/deadcode/DifferentAssumptionsOnReturnValuesTest.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/debug/ContinuousSteppingTest.java b/src/test/java/com/android/tools/r8/debug/ContinuousSteppingTest.java
index 9d33428..aac785c 100644
--- a/src/test/java/com/android/tools/r8/debug/ContinuousSteppingTest.java
+++ b/src/test/java/com/android/tools/r8/debug/ContinuousSteppingTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.ToolHelper.DexVm.Version;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.FileUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.android.tools.r8.utils.internal.collections.Pair;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableList.Builder;
diff --git a/src/test/java/com/android/tools/r8/debug/DebugStreamComparator.java b/src/test/java/com/android/tools/r8/debug/DebugStreamComparator.java
index 826de11..7ada0d6 100644
--- a/src/test/java/com/android/tools/r8/debug/DebugStreamComparator.java
+++ b/src/test/java/com/android/tools/r8/debug/DebugStreamComparator.java
@@ -11,8 +11,8 @@
 import com.android.tools.r8.debug.DebugTestBase.JUnit3Wrapper.DebuggeeState;
 import com.android.tools.r8.debug.DebugTestBase.JUnit3Wrapper.FrameInspector;
 import com.android.tools.r8.utils.ListUtils;
-import com.android.tools.r8.utils.StringUtils;
-import com.android.tools.r8.utils.StringUtils.BraceType;
+import com.android.tools.r8.utils.internal.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils.BraceType;
 import com.android.tools.r8.utils.internal.collections.Pair;
 import java.util.ArrayDeque;
 import java.util.ArrayList;
diff --git a/src/test/java/com/android/tools/r8/debug/ExamplesDebugTest.java b/src/test/java/com/android/tools/r8/debug/ExamplesDebugTest.java
index acb7c59..b3e4b98 100644
--- a/src/test/java/com/android/tools/r8/debug/ExamplesDebugTest.java
+++ b/src/test/java/com/android/tools/r8/debug/ExamplesDebugTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.ToolHelper.DexVm.Version;
 import com.android.tools.r8.debug.DebugTestBase.JUnit3Wrapper.DebuggeeState;
 import com.android.tools.r8.origin.Origin;
-import com.android.tools.r8.utils.FileUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Path;
 import java.nio.file.Paths;
diff --git a/src/test/java/com/android/tools/r8/debug/LambdaOuterContextTestRunner.java b/src/test/java/com/android/tools/r8/debug/LambdaOuterContextTestRunner.java
index 72f67f8..7226ec1 100644
--- a/src/test/java/com/android/tools/r8/debug/LambdaOuterContextTestRunner.java
+++ b/src/test/java/com/android/tools/r8/debug/LambdaOuterContextTestRunner.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.debug.LambdaOuterContextTest.Converter;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.apache.harmony.jpda.tests.framework.jdwp.Value;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/debuginfo/CanonicalConstantInPreambleTest.java b/src/test/java/com/android/tools/r8/debuginfo/CanonicalConstantInPreambleTest.java
index ab97b85..35e3200 100644
--- a/src/test/java/com/android/tools/r8/debuginfo/CanonicalConstantInPreambleTest.java
+++ b/src/test/java/com/android/tools/r8/debuginfo/CanonicalConstantInPreambleTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.cf.CfVersion;
 import com.android.tools.r8.transformers.ClassFileTransformer.MethodPredicate;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/debuginfo/DebugInfoInspector.java b/src/test/java/com/android/tools/r8/debuginfo/DebugInfoInspector.java
index ce48b16..bd28738 100644
--- a/src/test/java/com/android/tools/r8/debuginfo/DebugInfoInspector.java
+++ b/src/test/java/com/android/tools/r8/debuginfo/DebugInfoInspector.java
@@ -18,8 +18,8 @@
 import com.android.tools.r8.naming.MemberNaming.MethodSignature;
 import com.android.tools.r8.utils.AndroidApp;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.util.Collections;
 import java.util.HashSet;
diff --git a/src/test/java/com/android/tools/r8/debuginfo/OverloadWithNoLineNumberTest.java b/src/test/java/com/android/tools/r8/debuginfo/OverloadWithNoLineNumberTest.java
index d0a41c5..085368a 100644
--- a/src/test/java/com/android/tools/r8/debuginfo/OverloadWithNoLineNumberTest.java
+++ b/src/test/java/com/android/tools/r8/debuginfo/OverloadWithNoLineNumberTest.java
@@ -16,7 +16,7 @@
 import com.android.tools.r8.retrace.Retrace;
 import com.android.tools.r8.retrace.RetraceCommand;
 import com.android.tools.r8.transformers.ClassFileTransformer.MethodPredicate;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.stream.Collectors;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/debuginfo/Regress216178582Test.java b/src/test/java/com/android/tools/r8/debuginfo/Regress216178582Test.java
index 738f800..f879e88 100644
--- a/src/test/java/com/android/tools/r8/debuginfo/Regress216178582Test.java
+++ b/src/test/java/com/android/tools/r8/debuginfo/Regress216178582Test.java
@@ -4,7 +4,6 @@
 package com.android.tools.r8.debuginfo;
 
 import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertTrue;
 
 import com.android.tools.r8.TestBase;
@@ -16,7 +15,7 @@
 import com.android.tools.r8.graph.DexDebugEntryBuilder;
 import com.android.tools.r8.graph.DexDebugInfo;
 import com.android.tools.r8.graph.DexEncodedMethod;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.Iterator;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/debuginfo/SynchronizedMethodTestRunner.java b/src/test/java/com/android/tools/r8/debuginfo/SynchronizedMethodTestRunner.java
index f14d443..edf2029 100644
--- a/src/test/java/com/android/tools/r8/debuginfo/SynchronizedMethodTestRunner.java
+++ b/src/test/java/com/android/tools/r8/debuginfo/SynchronizedMethodTestRunner.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.utils.AndroidApp;
 import com.android.tools.r8.utils.AndroidAppConsumers;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.util.Arrays;
 import java.util.concurrent.ExecutionException;
diff --git a/src/test/java/com/android/tools/r8/debuginfo/composepc/ComposePcEncodingTest.java b/src/test/java/com/android/tools/r8/debuginfo/composepc/ComposePcEncodingTest.java
index 9c0f04a..641f7a1 100644
--- a/src/test/java/com/android/tools/r8/debuginfo/composepc/ComposePcEncodingTest.java
+++ b/src/test/java/com/android/tools/r8/debuginfo/composepc/ComposePcEncodingTest.java
@@ -22,8 +22,8 @@
 import com.android.tools.r8.retrace.RetraceStackTraceContext;
 import com.android.tools.r8.retrace.RetracedMethodReference;
 import com.android.tools.r8.transformers.ClassFileTransformer.MethodPredicate;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.FileUtils;
 import java.nio.file.Path;
 import java.util.OptionalInt;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/debuginfo/pc2pc/SharedPc2PcDebugInfo.java b/src/test/java/com/android/tools/r8/debuginfo/pc2pc/SharedPc2PcDebugInfo.java
index 105cb36..843a36e 100644
--- a/src/test/java/com/android/tools/r8/debuginfo/pc2pc/SharedPc2PcDebugInfo.java
+++ b/src/test/java/com/android/tools/r8/debuginfo/pc2pc/SharedPc2PcDebugInfo.java
@@ -11,8 +11,8 @@
 import com.android.tools.r8.graph.DexDebugInfo;
 import com.android.tools.r8.graph.DexEncodedMethod;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.PrintStream;
 import java.util.Arrays;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/desugar/BackportedMethodMergeTest.java b/src/test/java/com/android/tools/r8/desugar/BackportedMethodMergeTest.java
index 5dacf87..bcc99e4 100644
--- a/src/test/java/com/android/tools/r8/desugar/BackportedMethodMergeTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/BackportedMethodMergeTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.graph.ClassAccessFlags;
 import com.android.tools.r8.transformers.ClassTransformer;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/desugar/ConcurrentHashMapKeySetTest.java b/src/test/java/com/android/tools/r8/desugar/ConcurrentHashMapKeySetTest.java
index 6d9aac9..abd4cf2 100644
--- a/src/test/java/com/android/tools/r8/desugar/ConcurrentHashMapKeySetTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/ConcurrentHashMapKeySetTest.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRunResult;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.concurrent.ConcurrentHashMap;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/desugar/DefaultLambdaWithInvokeInterfaceTestRunner.java b/src/test/java/com/android/tools/r8/desugar/DefaultLambdaWithInvokeInterfaceTestRunner.java
index e9a894d..15dc1e5 100644
--- a/src/test/java/com/android/tools/r8/desugar/DefaultLambdaWithInvokeInterfaceTestRunner.java
+++ b/src/test/java/com/android/tools/r8/desugar/DefaultLambdaWithInvokeInterfaceTestRunner.java
@@ -16,7 +16,7 @@
 import com.android.tools.r8.references.MethodReference;
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.Collections;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/desugar/DefaultLambdaWithSelfReferenceTestRunner.java b/src/test/java/com/android/tools/r8/desugar/DefaultLambdaWithSelfReferenceTestRunner.java
index a4e0265..0d2c99b 100644
--- a/src/test/java/com/android/tools/r8/desugar/DefaultLambdaWithSelfReferenceTestRunner.java
+++ b/src/test/java/com/android/tools/r8/desugar/DefaultLambdaWithSelfReferenceTestRunner.java
@@ -18,7 +18,7 @@
 import com.android.tools.r8.debug.DebugTestConfig;
 import com.android.tools.r8.references.MethodReference;
 import com.android.tools.r8.references.Reference;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Files;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/desugar/DefaultLambdaWithUnderscoreThisTestRunner.java b/src/test/java/com/android/tools/r8/desugar/DefaultLambdaWithUnderscoreThisTestRunner.java
index 6bcd9f0..ec00e3c 100644
--- a/src/test/java/com/android/tools/r8/desugar/DefaultLambdaWithUnderscoreThisTestRunner.java
+++ b/src/test/java/com/android/tools/r8/desugar/DefaultLambdaWithUnderscoreThisTestRunner.java
@@ -16,7 +16,7 @@
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.InternalOptions.DesugarState;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.Collections;
 import java.util.function.Function;
diff --git a/src/test/java/com/android/tools/r8/desugar/DesugarInstanceLambdaWithReadsTest.java b/src/test/java/com/android/tools/r8/desugar/DesugarInstanceLambdaWithReadsTest.java
index f304791..0037db4 100644
--- a/src/test/java/com/android/tools/r8/desugar/DesugarInstanceLambdaWithReadsTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/DesugarInstanceLambdaWithReadsTest.java
@@ -11,10 +11,10 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FoundMethodSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/desugar/DesugarLambdaContextDuplicateInLibraryTest.java b/src/test/java/com/android/tools/r8/desugar/DesugarLambdaContextDuplicateInLibraryTest.java
index cd587f7..5f3a6db3 100644
--- a/src/test/java/com/android/tools/r8/desugar/DesugarLambdaContextDuplicateInLibraryTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/DesugarLambdaContextDuplicateInLibraryTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.errors.DuplicateTypeInProgramAndLibraryDiagnostic;
 import com.android.tools.r8.references.MethodReference;
 import com.android.tools.r8.references.Reference;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/desugar/DesugarMissingTypeClassTest.java b/src/test/java/com/android/tools/r8/desugar/DesugarMissingTypeClassTest.java
index f96c345..7e3502b 100644
--- a/src/test/java/com/android/tools/r8/desugar/DesugarMissingTypeClassTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/DesugarMissingTypeClassTest.java
@@ -18,7 +18,7 @@
 import com.android.tools.r8.position.Position;
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/desugar/DesugarMissingTypeLambdaTest.java b/src/test/java/com/android/tools/r8/desugar/DesugarMissingTypeLambdaTest.java
index d0dea4f..4f3df68 100644
--- a/src/test/java/com/android/tools/r8/desugar/DesugarMissingTypeLambdaTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/DesugarMissingTypeLambdaTest.java
@@ -19,7 +19,7 @@
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/desugar/DesugarMissingTypeStaticInvokeTest.java b/src/test/java/com/android/tools/r8/desugar/DesugarMissingTypeStaticInvokeTest.java
index d4c079c..90fca67 100644
--- a/src/test/java/com/android/tools/r8/desugar/DesugarMissingTypeStaticInvokeTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/DesugarMissingTypeStaticInvokeTest.java
@@ -20,7 +20,7 @@
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.MethodReferenceUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/desugar/DesugaredLambdaImplementationInliningTest.java b/src/test/java/com/android/tools/r8/desugar/DesugaredLambdaImplementationInliningTest.java
index 2041f10..048e2c4 100644
--- a/src/test/java/com/android/tools/r8/desugar/DesugaredLambdaImplementationInliningTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/DesugaredLambdaImplementationInliningTest.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/desugar/InterfaceInvokePrivateTest.java b/src/test/java/com/android/tools/r8/desugar/InterfaceInvokePrivateTest.java
index f44bb59..d908690 100644
--- a/src/test/java/com/android/tools/r8/desugar/InterfaceInvokePrivateTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/InterfaceInvokePrivateTest.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.cf.CfVersion;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/desugar/InvokeSuperToEmulatedDefaultMethodTest.java b/src/test/java/com/android/tools/r8/desugar/InvokeSuperToEmulatedDefaultMethodTest.java
index 2dd34a5..b6c9db5 100644
--- a/src/test/java/com/android/tools/r8/desugar/InvokeSuperToEmulatedDefaultMethodTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/InvokeSuperToEmulatedDefaultMethodTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.DesugaredLibraryTestBase;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.Collection;
 import java.util.HashMap;
diff --git a/src/test/java/com/android/tools/r8/desugar/InvokeSuperToRewrittenDefaultMethodTest.java b/src/test/java/com/android/tools/r8/desugar/InvokeSuperToRewrittenDefaultMethodTest.java
index eb211e6..46cdbbb 100644
--- a/src/test/java/com/android/tools/r8/desugar/InvokeSuperToRewrittenDefaultMethodTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/InvokeSuperToRewrittenDefaultMethodTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.DesugaredLibraryTestBase;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import java.util.function.Consumer;
diff --git a/src/test/java/com/android/tools/r8/desugar/LambdaHasNonSyntheticMethodTest.java b/src/test/java/com/android/tools/r8/desugar/LambdaHasNonSyntheticMethodTest.java
index c259adc..e294e7f 100644
--- a/src/test/java/com/android/tools/r8/desugar/LambdaHasNonSyntheticMethodTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/LambdaHasNonSyntheticMethodTest.java
@@ -6,7 +6,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.lang.reflect.Method;
 import java.lang.reflect.Modifier;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/desugar/LambdaWithDefaultMethodsTest.java b/src/test/java/com/android/tools/r8/desugar/LambdaWithDefaultMethodsTest.java
index 9066663..32ec763 100644
--- a/src/test/java/com/android/tools/r8/desugar/LambdaWithDefaultMethodsTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/LambdaWithDefaultMethodsTest.java
@@ -6,7 +6,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/desugar/MissingBridgeTest.java b/src/test/java/com/android/tools/r8/desugar/MissingBridgeTest.java
index 3dfd2fa..9f9f3c1 100644
--- a/src/test/java/com/android/tools/r8/desugar/MissingBridgeTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/MissingBridgeTest.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.graph.MethodAccessFlags;
 import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/desugar/VirtualInvokePrivateTest.java b/src/test/java/com/android/tools/r8/desugar/VirtualInvokePrivateTest.java
index 0b6c4e7..e13751d 100644
--- a/src/test/java/com/android/tools/r8/desugar/VirtualInvokePrivateTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/VirtualInvokePrivateTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.cf.CfVersion;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/desugar/backports/BackportDuplicationTest.java b/src/test/java/com/android/tools/r8/desugar/backports/BackportDuplicationTest.java
index 158ea70..0bc8f85 100644
--- a/src/test/java/com/android/tools/r8/desugar/backports/BackportDuplicationTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/backports/BackportDuplicationTest.java
@@ -30,9 +30,9 @@
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
 import com.android.tools.r8.synthesis.SyntheticNaming;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Sets;
diff --git a/src/test/java/com/android/tools/r8/desugar/backports/BackportMainDexTest.java b/src/test/java/com/android/tools/r8/desugar/backports/BackportMainDexTest.java
index dbde036..f117f6f 100644
--- a/src/test/java/com/android/tools/r8/desugar/backports/BackportMainDexTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/backports/BackportMainDexTest.java
@@ -28,8 +28,8 @@
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.AndroidApp;
 import com.android.tools.r8.utils.ListUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Sets;
diff --git a/src/test/java/com/android/tools/r8/desugar/backports/BackportPlatformTest.java b/src/test/java/com/android/tools/r8/desugar/backports/BackportPlatformTest.java
index 3b1f2a7..2671335 100644
--- a/src/test/java/com/android/tools/r8/desugar/backports/BackportPlatformTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/backports/BackportPlatformTest.java
@@ -18,7 +18,7 @@
 import com.android.tools.r8.desugar.backports.AbstractBackportTest.MiniAssert;
 import com.android.tools.r8.errors.IgnoredBackportMethodDiagnostic;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/desugar/backports/ThreadLocalBackportTest.java b/src/test/java/com/android/tools/r8/desugar/backports/ThreadLocalBackportTest.java
index 8fbadfa..117bb2c 100644
--- a/src/test/java/com/android/tools/r8/desugar/backports/ThreadLocalBackportTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/backports/ThreadLocalBackportTest.java
@@ -17,7 +17,7 @@
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.desugar.desugaredlibrary.DesugaredLibraryTestBase;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.function.Supplier;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/desugar/backports/ThreadLocalBackportWithDesugaredLibraryTest.java b/src/test/java/com/android/tools/r8/desugar/backports/ThreadLocalBackportWithDesugaredLibraryTest.java
index 67ee012..b522649 100644
--- a/src/test/java/com/android/tools/r8/desugar/backports/ThreadLocalBackportWithDesugaredLibraryTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/backports/ThreadLocalBackportWithDesugaredLibraryTest.java
@@ -15,7 +15,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.DesugaredLibraryTestBase;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/desugar/constantdynamic/BasicConstantDynamicTest.java b/src/test/java/com/android/tools/r8/desugar/constantdynamic/BasicConstantDynamicTest.java
index 6ed7eb2..616a001 100644
--- a/src/test/java/com/android/tools/r8/desugar/constantdynamic/BasicConstantDynamicTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/constantdynamic/BasicConstantDynamicTest.java
@@ -16,7 +16,7 @@
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.cf.CfVersion;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.lang.invoke.MethodHandles;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/desugar/constantdynamic/ConstantDynamicGetDeclaredMethodsTest.java b/src/test/java/com/android/tools/r8/desugar/constantdynamic/ConstantDynamicGetDeclaredMethodsTest.java
index 13615a0..14b4774 100644
--- a/src/test/java/com/android/tools/r8/desugar/constantdynamic/ConstantDynamicGetDeclaredMethodsTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/constantdynamic/ConstantDynamicGetDeclaredMethodsTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.ToolHelper.DexVm.Version;
 import com.android.tools.r8.cf.CfVersion;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.lang.invoke.MethodHandles;
 import java.lang.reflect.Method;
diff --git a/src/test/java/com/android/tools/r8/desugar/constantdynamic/ConstantDynamicInDefaultInterfaceMethodTest.java b/src/test/java/com/android/tools/r8/desugar/constantdynamic/ConstantDynamicInDefaultInterfaceMethodTest.java
index 02fedef..3cb96d6 100644
--- a/src/test/java/com/android/tools/r8/desugar/constantdynamic/ConstantDynamicInDefaultInterfaceMethodTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/constantdynamic/ConstantDynamicInDefaultInterfaceMethodTest.java
@@ -16,7 +16,7 @@
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.cf.CfVersion;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.lang.invoke.MethodHandles;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/desugar/constantdynamic/ConstantDynamicMultipleConstantsUsingSameSymbolicReferenceTest.java b/src/test/java/com/android/tools/r8/desugar/constantdynamic/ConstantDynamicMultipleConstantsUsingSameSymbolicReferenceTest.java
index bf8b736..f0ef4dc 100644
--- a/src/test/java/com/android/tools/r8/desugar/constantdynamic/ConstantDynamicMultipleConstantsUsingSameSymbolicReferenceTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/constantdynamic/ConstantDynamicMultipleConstantsUsingSameSymbolicReferenceTest.java
@@ -16,7 +16,7 @@
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.cf.CfVersion;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.lang.invoke.MethodHandles;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/desugar/constantdynamic/ConstantDynamicMultipleConstantsWithDifferentSymbolicReferenceUsingSameBSMAndArgumentsTest.java b/src/test/java/com/android/tools/r8/desugar/constantdynamic/ConstantDynamicMultipleConstantsWithDifferentSymbolicReferenceUsingSameBSMAndArgumentsTest.java
index 4d005cc..15dfb6c 100644
--- a/src/test/java/com/android/tools/r8/desugar/constantdynamic/ConstantDynamicMultipleConstantsWithDifferentSymbolicReferenceUsingSameBSMAndArgumentsTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/constantdynamic/ConstantDynamicMultipleConstantsWithDifferentSymbolicReferenceUsingSameBSMAndArgumentsTest.java
@@ -16,7 +16,7 @@
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.cf.CfVersion;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.lang.invoke.MethodHandles;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/desugar/constantdynamic/ConstantDynamicRegress272346803Test.java b/src/test/java/com/android/tools/r8/desugar/constantdynamic/ConstantDynamicRegress272346803Test.java
index e7a842c..2fe8089 100644
--- a/src/test/java/com/android/tools/r8/desugar/constantdynamic/ConstantDynamicRegress272346803Test.java
+++ b/src/test/java/com/android/tools/r8/desugar/constantdynamic/ConstantDynamicRegress272346803Test.java
@@ -16,7 +16,7 @@
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.cf.CfVersion;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.lang.invoke.MethodHandles;
 import java.util.Arrays;
diff --git a/src/test/java/com/android/tools/r8/desugar/constantdynamic/HierarchyConstantDynamicTest.java b/src/test/java/com/android/tools/r8/desugar/constantdynamic/HierarchyConstantDynamicTest.java
index 849a521..6f3a0ce 100644
--- a/src/test/java/com/android/tools/r8/desugar/constantdynamic/HierarchyConstantDynamicTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/constantdynamic/HierarchyConstantDynamicTest.java
@@ -15,7 +15,7 @@
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.cf.CfVersion;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.lang.invoke.MethodHandles;
diff --git a/src/test/java/com/android/tools/r8/desugar/constantdynamic/JacocoConstantDynamicGetDeclaredMethods.java b/src/test/java/com/android/tools/r8/desugar/constantdynamic/JacocoConstantDynamicGetDeclaredMethods.java
index 78d4db5..1386ef8 100644
--- a/src/test/java/com/android/tools/r8/desugar/constantdynamic/JacocoConstantDynamicGetDeclaredMethods.java
+++ b/src/test/java/com/android/tools/r8/desugar/constantdynamic/JacocoConstantDynamicGetDeclaredMethods.java
@@ -19,8 +19,8 @@
 import com.android.tools.r8.cf.CfVersion;
 import com.android.tools.r8.jacoco.JacocoClasses;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.lang.invoke.MethodHandles;
 import java.lang.reflect.Method;
diff --git a/src/test/java/com/android/tools/r8/desugar/constantdynamic/JacocoConstantDynamicTest.java b/src/test/java/com/android/tools/r8/desugar/constantdynamic/JacocoConstantDynamicTest.java
index 6385803..9c9aa98 100644
--- a/src/test/java/com/android/tools/r8/desugar/constantdynamic/JacocoConstantDynamicTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/constantdynamic/JacocoConstantDynamicTest.java
@@ -15,7 +15,7 @@
 import com.android.tools.r8.cf.CfVersion;
 import com.android.tools.r8.jacoco.JacocoClasses;
 import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.nio.file.Files;
diff --git a/src/test/java/com/android/tools/r8/desugar/constantdynamic/MultipleBootstrapMethodConstantDynamicTest.java b/src/test/java/com/android/tools/r8/desugar/constantdynamic/MultipleBootstrapMethodConstantDynamicTest.java
index 0e09283..cfa4bbd 100644
--- a/src/test/java/com/android/tools/r8/desugar/constantdynamic/MultipleBootstrapMethodConstantDynamicTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/constantdynamic/MultipleBootstrapMethodConstantDynamicTest.java
@@ -16,7 +16,7 @@
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.cf.CfVersion;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.lang.invoke.MethodHandles;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/desugar/constantdynamic/MultipleNamedConstantDynamicTest.java b/src/test/java/com/android/tools/r8/desugar/constantdynamic/MultipleNamedConstantDynamicTest.java
index c63486f..24bb7f4 100644
--- a/src/test/java/com/android/tools/r8/desugar/constantdynamic/MultipleNamedConstantDynamicTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/constantdynamic/MultipleNamedConstantDynamicTest.java
@@ -16,7 +16,7 @@
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.cf.CfVersion;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.lang.invoke.MethodHandles;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/desugar/constantdynamic/MultipleTypesConstantDynamicTest.java b/src/test/java/com/android/tools/r8/desugar/constantdynamic/MultipleTypesConstantDynamicTest.java
index 9871533..69e6030 100644
--- a/src/test/java/com/android/tools/r8/desugar/constantdynamic/MultipleTypesConstantDynamicTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/constantdynamic/MultipleTypesConstantDynamicTest.java
@@ -16,7 +16,7 @@
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.cf.CfVersion;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.lang.invoke.MethodHandles;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/desugar/constantdynamic/SharedBootstrapMethodConstantDynamicTest.java b/src/test/java/com/android/tools/r8/desugar/constantdynamic/SharedBootstrapMethodConstantDynamicTest.java
index 9fc702e..ae96d72 100644
--- a/src/test/java/com/android/tools/r8/desugar/constantdynamic/SharedBootstrapMethodConstantDynamicTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/constantdynamic/SharedBootstrapMethodConstantDynamicTest.java
@@ -23,7 +23,7 @@
 import com.android.tools.r8.errors.UnsupportedConstDynamicDiagnostic;
 import com.android.tools.r8.errors.UnsupportedFeatureDiagnostic;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.lang.invoke.MethodHandles;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/Base64Test.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/Base64Test.java
index 4afc01b..d0f200f 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/Base64Test.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/Base64Test.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.Base64;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/BufferedReaderTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/BufferedReaderTest.java
index 9e25257..006f37d 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/BufferedReaderTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/BufferedReaderTest.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.BufferedReader;
 import java.io.StringReader;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/ConcurrentHashMapSubclassTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/ConcurrentHashMapSubclassTest.java
index bcee062..a096d5f 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/ConcurrentHashMapSubclassTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/ConcurrentHashMapSubclassTest.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.IdentityHashMap;
 import java.util.List;
 import java.util.Map;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/ConcurrentHashMapSubclassV2Test.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/ConcurrentHashMapSubclassV2Test.java
index 8d84ddd..c5989e5 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/ConcurrentHashMapSubclassV2Test.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/ConcurrentHashMapSubclassV2Test.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import java.util.concurrent.ConcurrentHashMap;
 import org.junit.Assume;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/CustomCollectionForwardingTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/CustomCollectionForwardingTest.java
index 48c1d63..9cffaba 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/CustomCollectionForwardingTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/CustomCollectionForwardingTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Iterator;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/CustomCollectionInterfaceSuperTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/CustomCollectionInterfaceSuperTest.java
index 5d35c07..77c72db 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/CustomCollectionInterfaceSuperTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/CustomCollectionInterfaceSuperTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.Iterator;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/CustomMapHierarchyTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/CustomMapHierarchyTest.java
index 7306204..f7f6766 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/CustomMapHierarchyTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/CustomMapHierarchyTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DateInstantConversionTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DateInstantConversionTest.java
index 3c10a10..c74dedf 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DateInstantConversionTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DateInstantConversionTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.time.Instant;
 import java.util.Date;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DateTimeFormatterStandaloneMonthTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DateTimeFormatterStandaloneMonthTest.java
index 60f5174..237ca20 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DateTimeFormatterStandaloneMonthTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DateTimeFormatterStandaloneMonthTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.time.LocalDateTime;
 import java.time.format.DateTimeFormatter;
 import java.time.format.DateTimeFormatterBuilder;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DateTimeFormatterTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DateTimeFormatterTest.java
index ef27ccc..f6fb03d 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DateTimeFormatterTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DateTimeFormatterTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.time.LocalDateTime;
 import java.time.format.DateTimeFormatter;
 import java.time.format.DateTimeFormatterBuilder;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DateTimeStandaloneDayTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DateTimeStandaloneDayTest.java
index 629217e..c8ce070 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DateTimeStandaloneDayTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DateTimeStandaloneDayTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.time.DayOfWeek;
 import java.time.format.TextStyle;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DayTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DayTest.java
index ec68326..f657651 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DayTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DayTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.time.DayOfWeek;
 import java.time.format.TextStyle;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DefaultMethodOverrideInLibraryTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DefaultMethodOverrideInLibraryTest.java
index 1beb0ae..ffa144f 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DefaultMethodOverrideInLibraryTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DefaultMethodOverrideInLibraryTest.java
@@ -16,7 +16,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.lang.reflect.Method;
 import java.util.ArrayList;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DesugarCollectionsTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DesugarCollectionsTest.java
index a740261..78ec9b3 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DesugarCollectionsTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DesugarCollectionsTest.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.ArrayList;
 import java.util.Collection;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DesugaredGenericSignatureTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DesugaredGenericSignatureTest.java
index 7ba2614..2c882c1 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DesugaredGenericSignatureTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DesugaredGenericSignatureTest.java
@@ -17,9 +17,9 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.Serializable;
 import java.lang.reflect.ParameterizedType;
 import java.lang.reflect.Type;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DesugaredLibraryNavTypeTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DesugaredLibraryNavTypeTest.java
index 16b1f40..62c7a89 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DesugaredLibraryNavTypeTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DesugaredLibraryNavTypeTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.time.LocalDate;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DesugaredLocalDateReflectedTypePassedToStaticType.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DesugaredLocalDateReflectedTypePassedToStaticType.java
index 406ecc3..9e1332c 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DesugaredLocalDateReflectedTypePassedToStaticType.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DesugaredLocalDateReflectedTypePassedToStaticType.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.time.LocalDate;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DesugaredLocalDateReflectionTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DesugaredLocalDateReflectionTest.java
index 43dc91b..e8f8609 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DesugaredLocalDateReflectionTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DesugaredLocalDateReflectionTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.ToolHelper.DexVm;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DesugaredMethodsListTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DesugaredMethodsListTest.java
index 11a230c..b053f7d 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DesugaredMethodsListTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DesugaredMethodsListTest.java
@@ -20,8 +20,8 @@
 import com.android.tools.r8.ir.desugar.desugaredlibrary.lint.DesugaredMethodsList;
 import com.android.tools.r8.ir.desugar.desugaredlibrary.lint.GenerateDesugaredLibraryLintFiles;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.InternalOptions;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Path;
 import java.util.ArrayList;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DesugaredReflectedDesugaredTypePassedToStaticTypeTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DesugaredReflectedDesugaredTypePassedToStaticTypeTest.java
index ce83335..e5187b8 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DesugaredReflectedDesugaredTypePassedToStaticTypeTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DesugaredReflectedDesugaredTypePassedToStaticTypeTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.time.LocalDate;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DontKeepBootstrapClassesTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DontKeepBootstrapClassesTest.java
index dfc5e85..2eed7ca 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DontKeepBootstrapClassesTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/DontKeepBootstrapClassesTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CustomLibrarySpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 import java.util.function.Consumer;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/FeatureSplitTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/FeatureSplitTest.java
index 1b8aa3b..e4e1df2 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/FeatureSplitTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/FeatureSplitTest.java
@@ -22,8 +22,8 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.DesugaredLibraryTestCompileResult;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import dalvik.system.PathClassLoader;
 import java.io.IOException;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/FreezePeriodTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/FreezePeriodTest.java
index 4790305..67ba0a6 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/FreezePeriodTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/FreezePeriodTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CustomLibrarySpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.time.MonthDay;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/FunctionOnlyTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/FunctionOnlyTest.java
index 791a6b3..fb1cb4b 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/FunctionOnlyTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/FunctionOnlyTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import java.util.function.BiFunction;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/InvalidLibraryTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/InvalidLibraryTest.java
index d22793d..c1de805 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/InvalidLibraryTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/InvalidLibraryTest.java
@@ -17,7 +17,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.errors.InvalidLibrarySuperclassDiagnostic;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/IterableTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/IterableTest.java
index 5389a79..8fc5e9b 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/IterableTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/IterableTest.java
@@ -11,9 +11,9 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.CodeMatchers;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.Iterator;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/IterateTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/IterateTest.java
index b346e9e..edbe36d 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/IterateTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/IterateTest.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.transformers.MethodTransformer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import java.io.IOException;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/IteratorTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/IteratorTest.java
index 9f0f613..421ac3d 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/IteratorTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/IteratorTest.java
@@ -13,9 +13,9 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.Iterator;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/JavaTimeTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/JavaTimeTest.java
index cb628c6..230a321 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/JavaTimeTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/JavaTimeTest.java
@@ -18,7 +18,6 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.SetUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
@@ -26,6 +25,7 @@
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
 import com.android.tools.r8.utils.codeinspector.TryCatchSubject;
 import com.android.tools.r8.utils.codeinspector.TypeSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableSet;
 import java.time.DateTimeException;
 import java.time.ZoneId;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/JavaUtilFunctionTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/JavaUtilFunctionTest.java
index 0d661b2..463b5a1 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/JavaUtilFunctionTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/JavaUtilFunctionTest.java
@@ -17,9 +17,9 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableSet;
 import java.util.List;
 import java.util.function.Function;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/LegacyDesugaredLibraryConfigurationParsingTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/LegacyDesugaredLibraryConfigurationParsingTest.java
index a4fe87e..7e65850 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/LegacyDesugaredLibraryConfigurationParsingTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/LegacyDesugaredLibraryConfigurationParsingTest.java
@@ -29,8 +29,8 @@
 import com.android.tools.r8.utils.ListUtils;
 import com.android.tools.r8.utils.Reporter;
 import com.android.tools.r8.utils.internal.SemanticVersion;
-import com.android.tools.r8.utils.StringUtils;
-import com.android.tools.r8.utils.StringUtils.BraceType;
+import com.android.tools.r8.utils.internal.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils.BraceType;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import java.util.Collections;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/LintFilesTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/LintFilesTest.java
index b53dd78..3b98317 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/LintFilesTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/LintFilesTest.java
@@ -25,9 +25,9 @@
 import com.android.tools.r8.ir.desugar.desugaredlibrary.lint.GenerateDesugaredLibraryLintFiles;
 import com.android.tools.r8.ir.desugar.desugaredlibrary.lint.GenerateHtmlDoc;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.InternalOptions;
 import com.android.tools.r8.utils.Reporter;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Files;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/LocalDateEpochTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/LocalDateEpochTest.java
index 7b69be7..d310600 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/LocalDateEpochTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/LocalDateEpochTest.java
@@ -22,7 +22,7 @@
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.DescriptorUtils;
 import com.android.tools.r8.utils.InternalOptions;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.time.LocalDate;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/LocaleDateGetEraTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/LocaleDateGetEraTest.java
index 6798fb3..e569a87 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/LocaleDateGetEraTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/LocaleDateGetEraTest.java
@@ -17,7 +17,7 @@
 import com.android.tools.r8.transformers.MethodTransformer;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.time.LocalDate;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/MinimalInterfaceSuperTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/MinimalInterfaceSuperTest.java
index 8dbaa32..be5c857 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/MinimalInterfaceSuperTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/MinimalInterfaceSuperTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.AbstractCollection;
 import java.util.Collection;
 import java.util.Collections;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/MonthTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/MonthTest.java
index c17b621..55199c4 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/MonthTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/MonthTest.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.ToolHelper.DexVm.Version;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.time.Month;
 import java.time.format.TextStyle;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/NoDefaultMethodOverrideInLibraryTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/NoDefaultMethodOverrideInLibraryTest.java
index 263dbd7..11f52ab 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/NoDefaultMethodOverrideInLibraryTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/NoDefaultMethodOverrideInLibraryTest.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.lang.reflect.Method;
 import java.util.Collection;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/ObjectsTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/ObjectsTest.java
index add6c84..d93bee3 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/ObjectsTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/ObjectsTest.java
@@ -22,10 +22,10 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.Comparator;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/ProgramInterfaceWithLibraryMethod.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/ProgramInterfaceWithLibraryMethod.java
index f4d105c..a16d8d2 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/ProgramInterfaceWithLibraryMethod.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/ProgramInterfaceWithLibraryMethod.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CustomLibrarySpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import java.util.function.Consumer;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/ReleasedVersionsSmokeTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/ReleasedVersionsSmokeTest.java
index a343168..cb9b3da 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/ReleasedVersionsSmokeTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/ReleasedVersionsSmokeTest.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.time.Clock;
 import java.time.Duration;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/RequiredNonNullWithSupplierTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/RequiredNonNullWithSupplierTest.java
index 6a957ef..b6e0ea8 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/RequiredNonNullWithSupplierTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/RequiredNonNullWithSupplierTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import java.util.Objects;
 import java.util.function.Supplier;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/SimpleStreamPostPrefixTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/SimpleStreamPostPrefixTest.java
index 3515f94..f4f4e6e 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/SimpleStreamPostPrefixTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/SimpleStreamPostPrefixTest.java
@@ -12,10 +12,10 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.graph.DexType;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FoundMethodSubject;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.ArrayList;
 import java.util.IdentityHashMap;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/SimpleStreamTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/SimpleStreamTest.java
index 78a082c..d8f8290 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/SimpleStreamTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/SimpleStreamTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.stream.Collectors;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/SpliteratorTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/SpliteratorTest.java
index 3839d19..95d5982 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/SpliteratorTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/SpliteratorTest.java
@@ -12,8 +12,8 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.ArrayList;
 import java.util.Comparator;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/StaticInterfaceMethodTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/StaticInterfaceMethodTest.java
index d8f056b..f967001 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/StaticInterfaceMethodTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/StaticInterfaceMethodTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.time.chrono.Chronology;
 import java.util.List;
 import java.util.Map;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/TelemetryMapInterfaceTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/TelemetryMapInterfaceTest.java
index 174c311..e272360 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/TelemetryMapInterfaceTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/TelemetryMapInterfaceTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/APIConversionTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/APIConversionTest.java
index 8c7f50e..ec81f5a 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/APIConversionTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/APIConversionTest.java
@@ -17,7 +17,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.Arrays;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/AccessModeConversionTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/AccessModeConversionTest.java
index 5418edf..23e8261 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/AccessModeConversionTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/AccessModeConversionTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CustomLibrarySpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.AccessMode;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/AllOptionalConversionTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/AllOptionalConversionTest.java
index 2046f07..da0c5a3 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/AllOptionalConversionTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/AllOptionalConversionTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CustomLibrarySpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import java.util.Optional;
 import java.util.OptionalDouble;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/AllTimeConversionTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/AllTimeConversionTest.java
index 93ad54f..2b02595 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/AllTimeConversionTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/AllTimeConversionTest.java
@@ -17,7 +17,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CustomLibrarySpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.time.Duration;
 import java.time.Instant;
 import java.time.LocalDate;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/BasicLongDoubleConversionTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/BasicLongDoubleConversionTest.java
index 00766a5..bb0c4c8 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/BasicLongDoubleConversionTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/BasicLongDoubleConversionTest.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.time.MonthDay;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/CallBackConversionTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/CallBackConversionTest.java
index 2478d19..2361ee0 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/CallBackConversionTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/CallBackConversionTest.java
@@ -15,9 +15,9 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CustomLibrarySpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FoundMethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import java.util.function.Consumer;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/ClockAPIConversionTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/ClockAPIConversionTest.java
index b461d89..f0fabae 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/ClockAPIConversionTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/ClockAPIConversionTest.java
@@ -16,7 +16,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CustomLibrarySpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.time.Clock;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/ConversionAndMergeTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/ConversionAndMergeTest.java
index 1485859..eab5c70 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/ConversionAndMergeTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/ConversionAndMergeTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Path;
 import java.time.ZoneId;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/ConversionErrorMessageTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/ConversionErrorMessageTest.java
index 733603c..594c0e5 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/ConversionErrorMessageTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/ConversionErrorMessageTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.Arrays;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/ConversionIntroduceInterfaceMethodTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/ConversionIntroduceInterfaceMethodTest.java
index 24c66a2..8a61e88 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/ConversionIntroduceInterfaceMethodTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/ConversionIntroduceInterfaceMethodTest.java
@@ -16,11 +16,11 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CustomLibrarySpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FoundClassSubject;
 import com.android.tools.r8.utils.internal.BooleanUtils;
 import com.android.tools.r8.utils.internal.IterableUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.Iterator;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/DuplicateAPIDesugaredLibTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/DuplicateAPIDesugaredLibTest.java
index dc00d41..e957ae0 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/DuplicateAPIDesugaredLibTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/DuplicateAPIDesugaredLibTest.java
@@ -16,10 +16,10 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CustomLibrarySpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import java.util.Map;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/DuplicateAPIProgramTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/DuplicateAPIProgramTest.java
index bcb55fc..9f56126 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/DuplicateAPIProgramTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/DuplicateAPIProgramTest.java
@@ -14,8 +14,8 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CustomLibrarySpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.IdentityHashMap;
 import java.util.List;
 import java.util.Map;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/FileTimeConversionTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/FileTimeConversionTest.java
index 6145e65..0a8cdfd 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/FileTimeConversionTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/FileTimeConversionTest.java
@@ -18,10 +18,10 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.attribute.FileTime;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/FlatMapConversionTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/FlatMapConversionTest.java
index 5524f73..b80e7c6 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/FlatMapConversionTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/FlatMapConversionTest.java
@@ -19,7 +19,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CustomLibrarySpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.Arrays;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/FunctionConversionTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/FunctionConversionTest.java
index e284321..f44bd37 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/FunctionConversionTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/FunctionConversionTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CustomLibrarySpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import java.util.function.BiFunction;
 import java.util.function.BinaryOperator;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/MoreFunctionConversionTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/MoreFunctionConversionTest.java
index f5e298c..2540c32 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/MoreFunctionConversionTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/MoreFunctionConversionTest.java
@@ -16,9 +16,9 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.DesugaredLibraryTestCompileResult;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FoundClassSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.Sets;
 import java.util.List;
 import java.util.Set;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/SpliteratorConversionTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/SpliteratorConversionTest.java
index 54bcfbb..6b0f72c 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/SpliteratorConversionTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/SpliteratorConversionTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CustomLibrarySpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Spliterator;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/SummaryStatisticsConversionTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/SummaryStatisticsConversionTest.java
index 9dd62a9..d397542 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/SummaryStatisticsConversionTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/SummaryStatisticsConversionTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CustomLibrarySpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.DoubleSummaryStatistics;
 import java.util.IntSummaryStatistics;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/TimeConversionTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/TimeConversionTest.java
index 9f1c6d9..b09dc00 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/TimeConversionTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/TimeConversionTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CustomLibrarySpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.time.LocalDate;
 import java.time.LocalDateTime;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/TryCatchTimeConversionTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/TryCatchTimeConversionTest.java
index 5eb3dc6..0ec1f17 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/TryCatchTimeConversionTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/TryCatchTimeConversionTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CustomLibrarySpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.time.ZoneId;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/UnwrapConversionTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/UnwrapConversionTest.java
index e812cb6..1ce0471 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/UnwrapConversionTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/UnwrapConversionTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CustomLibrarySpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 import java.util.function.DoubleConsumer;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/WrapperEqualityTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/WrapperEqualityTest.java
index 773004d..f338eb7 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/WrapperEqualityTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/WrapperEqualityTest.java
@@ -16,7 +16,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CustomLibrarySpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/WrapperPlacementTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/WrapperPlacementTest.java
index d4e8306..7529cde 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/WrapperPlacementTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/conversiontests/WrapperPlacementTest.java
@@ -17,9 +17,9 @@
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
 import com.android.tools.r8.testing.AndroidBuildVersion;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FoundClassSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Path;
 import java.util.Arrays;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/customconversion/GenerateCustomConversionTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/customconversion/GenerateCustomConversionTest.java
index fb090bd..1816a9a 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/customconversion/GenerateCustomConversionTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/customconversion/GenerateCustomConversionTest.java
@@ -5,8 +5,8 @@
 package com.android.tools.r8.desugar.desugaredlibrary.customconversion;
 
 import static com.android.tools.r8.desugar.desugaredlibrary.DesugaredLibraryTestBase.getAllFilesWithSuffixInDirectory;
-import static com.android.tools.r8.utils.FileUtils.CLASS_EXTENSION;
-import static com.android.tools.r8.utils.FileUtils.JAVA_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.CLASS_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.JAVA_EXTENSION;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertTrue;
 
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/generation/GenerateDesugaredLibraryBridge.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/generation/GenerateDesugaredLibraryBridge.java
index 631d3ee..6d89253 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/generation/GenerateDesugaredLibraryBridge.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/generation/GenerateDesugaredLibraryBridge.java
@@ -15,7 +15,7 @@
 import com.android.tools.r8.graph.CfCode;
 import com.android.tools.r8.graph.DexType;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.FileUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import java.nio.charset.StandardCharsets;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/gson/ConcurrentHashMapFileSerializationTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/gson/ConcurrentHashMapFileSerializationTest.java
index 91669ae..2bfd77a 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/gson/ConcurrentHashMapFileSerializationTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/gson/ConcurrentHashMapFileSerializationTest.java
@@ -16,10 +16,10 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FieldSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.File;
 import java.io.FileInputStream;
 import java.io.FileOutputStream;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/gson/GsonEnumTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/gson/GsonEnumTest.java
index 716e3da..172de90 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/gson/GsonEnumTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/gson/GsonEnumTest.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.DesugaredLibraryTestBase;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.lang.reflect.Field;
 import java.time.chrono.IsoEra;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/gson/GsonOptionalTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/gson/GsonOptionalTest.java
index 639d27c..6476ee0 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/gson/GsonOptionalTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/gson/GsonOptionalTest.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.DesugaredLibraryTestBase;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/gson/MyMapFileSerializationTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/gson/MyMapFileSerializationTest.java
index 2387d64..c66fa88 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/gson/MyMapFileSerializationTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/gson/MyMapFileSerializationTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.DesugaredLibraryTestBase;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.File;
 import java.io.FileInputStream;
 import java.io.FileOutputStream;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/gson/TimeSerializationTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/gson/TimeSerializationTest.java
index 5c87fb9..d94d584 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/gson/TimeSerializationTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/gson/TimeSerializationTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.DesugaredLibraryTestBase;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.File;
 import java.io.FileInputStream;
 import java.io.FileOutputStream;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/ChannelSetTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/ChannelSetTest.java
index cc4bbc3..1bc0a01 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/ChannelSetTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/ChannelSetTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CustomLibrarySpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.nio.ByteBuffer;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/ConcurrentHashMapJDK11Test.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/ConcurrentHashMapJDK11Test.java
index 07c7067..5d29f9d 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/ConcurrentHashMapJDK11Test.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/ConcurrentHashMapJDK11Test.java
@@ -15,7 +15,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CustomLibrarySpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import java.util.concurrent.ConcurrentHashMap;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FileChannelSizeTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FileChannelSizeTest.java
index 5b55897..4d6aca2 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FileChannelSizeTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FileChannelSizeTest.java
@@ -15,7 +15,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.File;
 import java.io.FileInputStream;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FileChannelTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FileChannelTest.java
index 6219ccd..3d36333 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FileChannelTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FileChannelTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.DesugaredLibraryTestBase;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.FileDescriptor;
 import java.io.FileInputStream;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FileLockTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FileLockTest.java
index 2ea0a50..9796b98 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FileLockTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FileLockTest.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.DesugaredLibraryTestBase;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.FileOutputStream;
 import java.io.IOException;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FileTypeDetectorTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FileTypeDetectorTest.java
index a99b028..b85e54a 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FileTypeDetectorTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FileTypeDetectorTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.DesugaredLibraryTestBase;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.io.InputStream;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FilesAttributes2Test.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FilesAttributes2Test.java
index a7502d5..a200188 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FilesAttributes2Test.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FilesAttributes2Test.java
@@ -17,7 +17,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.DesugaredLibraryTestCompileResult;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Files;
 import java.nio.file.LinkOption;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FilesAttributesTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FilesAttributesTest.java
index 4c0b7d9..291296b 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FilesAttributesTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FilesAttributesTest.java
@@ -15,7 +15,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.DesugaredLibraryTestBase;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Files;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FilesBlogTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FilesBlogTest.java
index 4a59c63..99daabe 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FilesBlogTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FilesBlogTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.DesugaredLibraryTestBase;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FilesCreateTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FilesCreateTest.java
index a1faf48..01cd55b 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FilesCreateTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FilesCreateTest.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.DesugaredLibraryTestBase;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.File;
 import java.nio.file.Files;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FilesInOutTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FilesInOutTest.java
index bbfcb4a..06ed399 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FilesInOutTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FilesInOutTest.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.DesugaredLibraryTestBase;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.BufferedReader;
 import java.io.BufferedWriter;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FilesMoveCopyTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FilesMoveCopyTest.java
index eed1149..70afe26 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FilesMoveCopyTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FilesMoveCopyTest.java
@@ -20,7 +20,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.DesugaredLibraryTestBase;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.FileInputStream;
 import java.io.FileOutputStream;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FilesSymLinkTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FilesSymLinkTest.java
index 4ec83cb..cd2167f 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FilesSymLinkTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FilesSymLinkTest.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.DesugaredLibraryTestBase;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Files;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FilesTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FilesTest.java
index 3b08a7e..2440da1 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FilesTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FilesTest.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.DesugaredLibraryTestBase;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.nio.ByteBuffer;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FilesVisitTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FilesVisitTest.java
index 7b5eb9a..cc0f588 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FilesVisitTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FilesVisitTest.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.DesugaredLibraryTestBase;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.nio.file.FileVisitOption;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FilesWatchEventTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FilesWatchEventTest.java
index 95d50fa..137e482 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FilesWatchEventTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/FilesWatchEventTest.java
@@ -15,7 +15,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.DesugaredLibraryTestBase;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.nio.file.FileSystem;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/JavaTimeJDK11Test.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/JavaTimeJDK11Test.java
index ca28ae8..57d8828 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/JavaTimeJDK11Test.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/JavaTimeJDK11Test.java
@@ -17,10 +17,10 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.transformers.MethodTransformer;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 import java.io.IOException;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/PathTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/PathTest.java
index 699cd7f..524b34a 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/PathTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/PathTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.DesugaredLibraryTestBase;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.File;
 import java.io.IOException;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/StandardCharsetTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/StandardCharsetTest.java
index 181cd69..dc6b616 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/StandardCharsetTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/StandardCharsetTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.transformers.MethodTransformer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.nio.charset.Charset;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/StreamCollectorCharacteristicsTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/StreamCollectorCharacteristicsTest.java
index 0d44dc3..f7a31aa 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/StreamCollectorCharacteristicsTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdk11/StreamCollectorCharacteristicsTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CustomLibrarySpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import java.util.stream.Collector;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdktests/Jdk11AtomicTests.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdktests/Jdk11AtomicTests.java
index 3ac00b5..900453a 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdktests/Jdk11AtomicTests.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdktests/Jdk11AtomicTests.java
@@ -13,8 +13,8 @@
 import static com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification.JDK11;
 import static com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification.JDK11_PATH;
 import static com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification.JDK8;
-import static com.android.tools.r8.utils.FileUtils.CLASS_EXTENSION;
-import static com.android.tools.r8.utils.FileUtils.JAVA_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.CLASS_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.JAVA_EXTENSION;
 import static org.hamcrest.CoreMatchers.endsWith;
 
 import com.android.tools.r8.TestParameters;
@@ -24,7 +24,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.DesugaredLibraryTestBase;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Path;
 import java.nio.file.Paths;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdktests/Jdk11ConcurrentLinkedQueueTests.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdktests/Jdk11ConcurrentLinkedQueueTests.java
index af9434d..43df693 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdktests/Jdk11ConcurrentLinkedQueueTests.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdktests/Jdk11ConcurrentLinkedQueueTests.java
@@ -12,9 +12,9 @@
 import static com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification.JDK11;
 import static com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification.JDK11_MINIMAL;
 import static com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification.JDK11_PATH;
-import static com.android.tools.r8.utils.FileUtils.CLASS_EXTENSION;
-import static com.android.tools.r8.utils.FileUtils.JAVA_EXTENSION;
 import static com.android.tools.r8.utils.codeinspector.Matchers.isPresent;
+import static com.android.tools.r8.utils.internal.FileUtils.CLASS_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.JAVA_EXTENSION;
 import static org.hamcrest.CoreMatchers.not;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.junit.Assert.assertTrue;
@@ -35,8 +35,8 @@
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdktests/Jdk11ConcurrentMapTests.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdktests/Jdk11ConcurrentMapTests.java
index c27bb8b..d13e34e 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdktests/Jdk11ConcurrentMapTests.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdktests/Jdk11ConcurrentMapTests.java
@@ -13,8 +13,8 @@
 import static com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification.JDK11;
 import static com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification.JDK11_PATH;
 import static com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification.JDK8;
-import static com.android.tools.r8.utils.FileUtils.CLASS_EXTENSION;
-import static com.android.tools.r8.utils.FileUtils.JAVA_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.CLASS_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.JAVA_EXTENSION;
 import static org.hamcrest.CoreMatchers.endsWith;
 
 import com.android.tools.r8.TestParameters;
@@ -25,7 +25,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.DesugaredLibraryTestCompileResult;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Path;
 import java.nio.file.Paths;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdktests/Jdk11MathTests.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdktests/Jdk11MathTests.java
index 05b4d1d..fc4ea3c 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdktests/Jdk11MathTests.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdktests/Jdk11MathTests.java
@@ -4,8 +4,8 @@
 
 package com.android.tools.r8.desugar.desugaredlibrary.jdktests;
 
-import static com.android.tools.r8.utils.FileUtils.CLASS_EXTENSION;
-import static com.android.tools.r8.utils.FileUtils.JAVA_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.CLASS_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.JAVA_EXTENSION;
 
 import com.android.tools.r8.Jdk9TestUtils;
 import com.android.tools.r8.TestBase;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdktests/Jdk11NameLimitsTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdktests/Jdk11NameLimitsTest.java
index 44e6911..ce95f56 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdktests/Jdk11NameLimitsTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdktests/Jdk11NameLimitsTest.java
@@ -6,7 +6,7 @@
 
 import static com.android.tools.r8.desugar.desugaredlibrary.jdktests.Jdk11TestLibraryDesugaringSpecification.EXTENSION_PATH;
 import static com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification.DEFAULT_SPECIFICATIONS;
-import static com.android.tools.r8.utils.FileUtils.CLASS_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.CLASS_EXTENSION;
 
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestRuntime;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdktests/Jdk11NioFileTests.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdktests/Jdk11NioFileTests.java
index 200d907..dbd69dd 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdktests/Jdk11NioFileTests.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdktests/Jdk11NioFileTests.java
@@ -11,8 +11,8 @@
 import static com.android.tools.r8.desugar.desugaredlibrary.jdktests.Jdk11TestLibraryDesugaringSpecification.JDK11_PATH_JAVA_BASE_EXT;
 import static com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification.D8_L8DEBUG;
 import static com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification.D8_L8SHRINK;
-import static com.android.tools.r8.utils.FileUtils.CLASS_EXTENSION;
-import static com.android.tools.r8.utils.FileUtils.JAVA_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.CLASS_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.JAVA_EXTENSION;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertTrue;
 
@@ -30,7 +30,7 @@
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.transformers.ClassFileTransformer;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 import java.io.IOException;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdktests/Jdk11ObjectsTests.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdktests/Jdk11ObjectsTests.java
index 2a5a982..18c5815 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdktests/Jdk11ObjectsTests.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdktests/Jdk11ObjectsTests.java
@@ -4,8 +4,8 @@
 
 package com.android.tools.r8.desugar.desugaredlibrary.jdktests;
 
-import static com.android.tools.r8.utils.FileUtils.CLASS_EXTENSION;
-import static com.android.tools.r8.utils.FileUtils.JAVA_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.CLASS_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.JAVA_EXTENSION;
 
 import com.android.tools.r8.Jdk9TestUtils;
 import com.android.tools.r8.TestBase;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdktests/Jdk11StreamAbstractTests.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdktests/Jdk11StreamAbstractTests.java
index e24ede9..a30d61e 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdktests/Jdk11StreamAbstractTests.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdktests/Jdk11StreamAbstractTests.java
@@ -14,8 +14,8 @@
 import static com.android.tools.r8.desugar.desugaredlibrary.jdktests.Jdk11TestLibraryDesugaringSpecification.JDK8_JAVA_BASE_EXT;
 import static com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification.D8CF2CF_L8DEBUG;
 import static com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification.D8_L8SHRINK;
-import static com.android.tools.r8.utils.FileUtils.CLASS_EXTENSION;
-import static com.android.tools.r8.utils.FileUtils.JAVA_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.CLASS_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.JAVA_EXTENSION;
 import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.fail;
 import static org.junit.Assume.assumeTrue;
@@ -30,7 +30,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.DesugaredLibraryTestCompileResult;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Path;
 import java.nio.file.Paths;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdktests/Jdk11TestLibraryDesugaringSpecification.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdktests/Jdk11TestLibraryDesugaringSpecification.java
index 4abd316..ec00482 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdktests/Jdk11TestLibraryDesugaringSpecification.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdktests/Jdk11TestLibraryDesugaringSpecification.java
@@ -9,7 +9,7 @@
 import static com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification.JDK11;
 import static com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification.JDK11_PATH;
 import static com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification.JDK8;
-import static com.android.tools.r8.utils.FileUtils.JAVA_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.JAVA_EXTENSION;
 
 import com.android.tools.r8.JavaCompilerTool;
 import com.android.tools.r8.TestRuntime;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdktests/Jdk11TimeAbstractTests.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdktests/Jdk11TimeAbstractTests.java
index befef28..1ba8698 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdktests/Jdk11TimeAbstractTests.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/jdktests/Jdk11TimeAbstractTests.java
@@ -14,8 +14,8 @@
 import static com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification.D8_L8SHRINK;
 import static com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification.JDK11_PATH;
 import static com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification.JDK8;
-import static com.android.tools.r8.utils.FileUtils.CLASS_EXTENSION;
-import static com.android.tools.r8.utils.FileUtils.JAVA_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.CLASS_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.JAVA_EXTENSION;
 import static org.junit.Assert.assertTrue;
 
 import com.android.tools.r8.SingleTestRunResult;
@@ -28,7 +28,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.DesugaredLibraryTestCompileResult;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Files;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/kotlin/KotlinBlogTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/kotlin/KotlinBlogTest.java
index 835d2dc..8af7bb7 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/kotlin/KotlinBlogTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/kotlin/KotlinBlogTest.java
@@ -20,8 +20,8 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Paths;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/kotlin/KotlinMetadataTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/kotlin/KotlinMetadataTest.java
index c2501ac..5bcfe4e 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/kotlin/KotlinMetadataTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/kotlin/KotlinMetadataTest.java
@@ -25,11 +25,11 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.kotlin.KotlinMetadataWriter;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
-import com.android.tools.r8.utils.internal.ConsumerUtils;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.ConsumerUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Paths;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/legacy/L8TestWithLegacySpecification.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/legacy/L8TestWithLegacySpecification.java
index dd08c9e..2a0c3de 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/legacy/L8TestWithLegacySpecification.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/legacy/L8TestWithLegacySpecification.java
@@ -12,8 +12,8 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.charset.StandardCharsets;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/shrinkingtests/EnumSetTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/shrinkingtests/EnumSetTest.java
index 6c691dd..ba236dd 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/shrinkingtests/EnumSetTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/shrinkingtests/EnumSetTest.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.DesugaredLibraryTestBase;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.time.DayOfWeek;
 import java.time.chrono.IsoEra;
 import java.time.chrono.MinguoEra;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/shrinkingtests/FieldAccessTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/shrinkingtests/FieldAccessTest.java
index 3f1c8cb..e09d130 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/shrinkingtests/FieldAccessTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/shrinkingtests/FieldAccessTest.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.DesugaredLibraryTestBase;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.time.ZoneId;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/shrinkingtests/InheritanceTest.java b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/shrinkingtests/InheritanceTest.java
index 899bd19..f8dfbf4 100644
--- a/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/shrinkingtests/InheritanceTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/desugaredlibrary/shrinkingtests/InheritanceTest.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.DesugaredLibraryTestBase;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.time.Clock;
 import java.time.Instant;
 import java.time.ZoneId;
diff --git a/src/test/java/com/android/tools/r8/desugar/graph/InterfaceBridgeDependencyTest.java b/src/test/java/com/android/tools/r8/desugar/graph/InterfaceBridgeDependencyTest.java
index bfd0048..7aeae94 100644
--- a/src/test/java/com/android/tools/r8/desugar/graph/InterfaceBridgeDependencyTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/graph/InterfaceBridgeDependencyTest.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaEqualityTest.java b/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaEqualityTest.java
index dd5f654..879ee57 100644
--- a/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaEqualityTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaEqualityTest.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.references.Reference;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaFactoryTest.java b/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaFactoryTest.java
index d92808b..fabbfb1 100644
--- a/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaFactoryTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaFactoryTest.java
@@ -13,10 +13,10 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
 import com.android.tools.r8.utils.InternalOptions;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaInStacktraceTest.java b/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaInStacktraceTest.java
index 1aeff4d..533a4f8 100644
--- a/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaInStacktraceTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaInStacktraceTest.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.concurrent.Callable;
diff --git a/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaMethodsWithModifiedAccessTest.java b/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaMethodsWithModifiedAccessTest.java
index a63b129..19c861c 100644
--- a/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaMethodsWithModifiedAccessTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaMethodsWithModifiedAccessTest.java
@@ -16,8 +16,8 @@
 import com.android.tools.r8.graph.AccessFlags;
 import com.android.tools.r8.graph.MethodAccessFlags;
 import com.android.tools.r8.transformers.ClassFileTransformer.MethodPredicate;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.util.function.Function;
 import org.junit.BeforeClass;
diff --git a/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaNamingConflictTest.java b/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaNamingConflictTest.java
index 696a30e..a0cd432 100644
--- a/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaNamingConflictTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaNamingConflictTest.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.references.ClassReference;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.BeforeClass;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaPrivateStaticMethodTest.java b/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaPrivateStaticMethodTest.java
index 780d2ee..e70ff4c 100644
--- a/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaPrivateStaticMethodTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaPrivateStaticMethodTest.java
@@ -6,7 +6,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaStaticInstanceFieldDuplicationTest.java b/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaStaticInstanceFieldDuplicationTest.java
index c01d5fe..aa562e1 100644
--- a/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaStaticInstanceFieldDuplicationTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaStaticInstanceFieldDuplicationTest.java
@@ -15,9 +15,9 @@
 import com.android.tools.r8.references.MethodReference;
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Sets;
diff --git a/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaToSysOutPrintlnDuplicationTest.java b/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaToSysOutPrintlnDuplicationTest.java
index b1f46c7..a3e6f7d 100644
--- a/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaToSysOutPrintlnDuplicationTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaToSysOutPrintlnDuplicationTest.java
@@ -15,9 +15,9 @@
 import com.android.tools.r8.references.MethodReference;
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Sets;
diff --git a/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaWithPrimitiveReferenceTypeConflictTest.java b/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaWithPrimitiveReferenceTypeConflictTest.java
index b357ea8..676963e 100644
--- a/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaWithPrimitiveReferenceTypeConflictTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaWithPrimitiveReferenceTypeConflictTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.lang.invoke.LambdaConversionException;
diff --git a/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaWithPrimitiveReferenceTypeConflictWideTest.java b/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaWithPrimitiveReferenceTypeConflictWideTest.java
index 2cb8af2..1c045a3 100644
--- a/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaWithPrimitiveReferenceTypeConflictWideTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaWithPrimitiveReferenceTypeConflictWideTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.lang.invoke.LambdaConversionException;
diff --git a/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaWithPrivateInterfaceInvokeTest.java b/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaWithPrivateInterfaceInvokeTest.java
index 77a64a4..a868f07 100644
--- a/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaWithPrivateInterfaceInvokeTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/lambdas/LambdaWithPrivateInterfaceInvokeTest.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/desugar/lambdas/LambdasInHugeMethodTest.java b/src/test/java/com/android/tools/r8/desugar/lambdas/LambdasInHugeMethodTest.java
index 3827726..0f65275 100644
--- a/src/test/java/com/android/tools/r8/desugar/lambdas/LambdasInHugeMethodTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/lambdas/LambdasInHugeMethodTest.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.transformers.ClassFileTransformer.MethodPredicate;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.ArrayList;
 import java.util.List;
 import org.junit.jupiter.api.Test;
diff --git a/src/test/java/com/android/tools/r8/desugar/lambdas/LegacyLambdaMergeTest.java b/src/test/java/com/android/tools/r8/desugar/lambdas/LegacyLambdaMergeTest.java
index e4ba6bf..a926e46 100644
--- a/src/test/java/com/android/tools/r8/desugar/lambdas/LegacyLambdaMergeTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/lambdas/LegacyLambdaMergeTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.transformers.ClassFileTransformer.MethodInsnTransform;
 import com.android.tools.r8.transformers.ClassFileTransformer.TypeInsnTransform;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/desugar/lambdas/OverlappingLambdaMethodInSubclassWithSameNameTest.java b/src/test/java/com/android/tools/r8/desugar/lambdas/OverlappingLambdaMethodInSubclassWithSameNameTest.java
index a2edc18..2de8746 100644
--- a/src/test/java/com/android/tools/r8/desugar/lambdas/OverlappingLambdaMethodInSubclassWithSameNameTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/lambdas/OverlappingLambdaMethodInSubclassWithSameNameTest.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.desugar.lambdas.b197625454.OverlappingLambdaMethodInSubclassWithSameNameTestA;
 import com.android.tools.r8.desugar.lambdas.b197625454.OverlappingLambdaMethodInSubclassWithSameNameTestB;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/desugar/nestaccesscontrol/NestPrivateInterfaceMethodsTest.java b/src/test/java/com/android/tools/r8/desugar/nestaccesscontrol/NestPrivateInterfaceMethodsTest.java
index 2e5a3fc..b43e071 100644
--- a/src/test/java/com/android/tools/r8/desugar/nestaccesscontrol/NestPrivateInterfaceMethodsTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/nestaccesscontrol/NestPrivateInterfaceMethodsTest.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/desugar/records/GenerateRecordMethods.java b/src/test/java/com/android/tools/r8/desugar/records/GenerateRecordMethods.java
index 1f01b2c..91a1b2d 100644
--- a/src/test/java/com/android/tools/r8/desugar/records/GenerateRecordMethods.java
+++ b/src/test/java/com/android/tools/r8/desugar/records/GenerateRecordMethods.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.ToolHelper.TestDataSourceSet;
 import com.android.tools.r8.cfmethodgeneration.MethodGenerationBase;
 import com.android.tools.r8.graph.DexType;
-import com.android.tools.r8.utils.FileUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.charset.StandardCharsets;
 import java.util.ArrayList;
diff --git a/src/test/java/com/android/tools/r8/desugar/sealed/PermittedSubclassesAttributeInDexTest.java b/src/test/java/com/android/tools/r8/desugar/sealed/PermittedSubclassesAttributeInDexTest.java
index 4435deb..091e29f 100644
--- a/src/test/java/com/android/tools/r8/desugar/sealed/PermittedSubclassesAttributeInDexTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/sealed/PermittedSubclassesAttributeInDexTest.java
@@ -15,8 +15,8 @@
 import com.android.tools.r8.transformers.ClassFileTransformer;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Path;
 import java.util.Arrays;
diff --git a/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesEnumImplementsTest.java b/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesEnumImplementsTest.java
index 5dfa559..839c9d7 100644
--- a/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesEnumImplementsTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesEnumImplementsTest.java
@@ -17,10 +17,10 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.TestShrinkerBuilder;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesExtendsTest.java b/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesExtendsTest.java
index 02f90c0..1f00826 100644
--- a/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesExtendsTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesExtendsTest.java
@@ -17,10 +17,10 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.TestShrinkerBuilder;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesExtendsVerticalMergeTest.java b/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesExtendsVerticalMergeTest.java
index f43d0ac..dc55d5e 100644
--- a/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesExtendsVerticalMergeTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesExtendsVerticalMergeTest.java
@@ -12,10 +12,10 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.HorizontallyMergedClassesInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesHorizontalMergeTest.java b/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesHorizontalMergeTest.java
index 0a5027f..880f68a 100644
--- a/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesHorizontalMergeTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesHorizontalMergeTest.java
@@ -12,9 +12,9 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesIllegalSubclassMergedTest.java b/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesIllegalSubclassMergedTest.java
index 5bb51eb..bcf7fd5 100644
--- a/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesIllegalSubclassMergedTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesIllegalSubclassMergedTest.java
@@ -15,9 +15,9 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import org.hamcrest.Matcher;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesIllegalSubclassTest.java b/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesIllegalSubclassTest.java
index bfacde8..7e6afc8 100644
--- a/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesIllegalSubclassTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesIllegalSubclassTest.java
@@ -18,10 +18,10 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.TestShrinkerBuilder;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.hamcrest.Matcher;
diff --git a/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesImplementsTest.java b/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesImplementsTest.java
index 0204278..cfb86a4 100644
--- a/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesImplementsTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesImplementsTest.java
@@ -15,12 +15,12 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.TestShrinkerBuilder;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.HorizontallyMergedClassesInspector;
 import com.android.tools.r8.utils.codeinspector.VerticallyMergedClassesInspector;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesImplementsVerticalMergeTest.java b/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesImplementsVerticalMergeTest.java
index 45ccb0d..7d03223 100644
--- a/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesImplementsVerticalMergeTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesImplementsVerticalMergeTest.java
@@ -14,11 +14,11 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.HorizontallyMergedClassesInspector;
 import com.android.tools.r8.utils.codeinspector.Matchers;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesMergeTest.java b/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesMergeTest.java
index 19a37fc..a9359b0 100644
--- a/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesMergeTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesMergeTest.java
@@ -13,9 +13,9 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesShrinkingTest.java b/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesShrinkingTest.java
index 201bc2d..94a589f 100644
--- a/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesShrinkingTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesShrinkingTest.java
@@ -13,9 +13,9 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesTestAllowPermittedSubclassesRemovalTest.java b/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesTestAllowPermittedSubclassesRemovalTest.java
index 350f1f7..2352996 100644
--- a/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesTestAllowPermittedSubclassesRemovalTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/sealed/SealedClassesTestAllowPermittedSubclassesRemovalTest.java
@@ -12,10 +12,10 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.Matchers;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/desugar/staticinterfacemethod/MutuallyRecursiveMethodsTest.java b/src/test/java/com/android/tools/r8/desugar/staticinterfacemethod/MutuallyRecursiveMethodsTest.java
index 662eac3..f252c42 100644
--- a/src/test/java/com/android/tools/r8/desugar/staticinterfacemethod/MutuallyRecursiveMethodsTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/staticinterfacemethod/MutuallyRecursiveMethodsTest.java
@@ -6,7 +6,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/desugar/suppressedexceptions/SuppressedExceptionsTest.java b/src/test/java/com/android/tools/r8/desugar/suppressedexceptions/SuppressedExceptionsTest.java
index 2c6e284..0b739d6 100644
--- a/src/test/java/com/android/tools/r8/desugar/suppressedexceptions/SuppressedExceptionsTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/suppressedexceptions/SuppressedExceptionsTest.java
@@ -10,10 +10,10 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ToolHelper.DexVm.Version;
-import com.android.tools.r8.utils.internal.IntBox;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.IntBox;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import java.util.stream.Collectors;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/desugar/twr/CheckTwrOutputForJavaCompilersTest.java b/src/test/java/com/android/tools/r8/desugar/twr/CheckTwrOutputForJavaCompilersTest.java
index cc6a5ca..9a4ac1b 100644
--- a/src/test/java/com/android/tools/r8/desugar/twr/CheckTwrOutputForJavaCompilersTest.java
+++ b/src/test/java/com/android/tools/r8/desugar/twr/CheckTwrOutputForJavaCompilersTest.java
@@ -11,9 +11,9 @@
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableSet;
 import java.nio.file.Path;
 import java.util.Collections;
diff --git a/src/test/java/com/android/tools/r8/desugaring/interfacemethods/CompanionClassNoSignatureTest.java b/src/test/java/com/android/tools/r8/desugaring/interfacemethods/CompanionClassNoSignatureTest.java
index 47b8383..036f6e9 100644
--- a/src/test/java/com/android/tools/r8/desugaring/interfacemethods/CompanionClassNoSignatureTest.java
+++ b/src/test/java/com/android/tools/r8/desugaring/interfacemethods/CompanionClassNoSignatureTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.graph.GenericSignature.ClassSignature;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/desugaring/interfacemethods/CompanionClassWithSignatureTest.java b/src/test/java/com/android/tools/r8/desugaring/interfacemethods/CompanionClassWithSignatureTest.java
index 060af3f..74d1ee0 100644
--- a/src/test/java/com/android/tools/r8/desugaring/interfacemethods/CompanionClassWithSignatureTest.java
+++ b/src/test/java/com/android/tools/r8/desugaring/interfacemethods/CompanionClassWithSignatureTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ToolHelper.DexVm.Version;
 import com.android.tools.r8.graph.GenericSignature.ClassSignature;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/desugaring/interfacemethods/DefaultInterfaceMethodDesugaringImpossibleTest.java b/src/test/java/com/android/tools/r8/desugaring/interfacemethods/DefaultInterfaceMethodDesugaringImpossibleTest.java
index 3be277e..64da820 100644
--- a/src/test/java/com/android/tools/r8/desugaring/interfacemethods/DefaultInterfaceMethodDesugaringImpossibleTest.java
+++ b/src/test/java/com/android/tools/r8/desugaring/interfacemethods/DefaultInterfaceMethodDesugaringImpossibleTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestDiagnosticMessages;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.Collection;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/desugaring/interfacemethods/DefaultInterfaceMethodDesugaringWithPrivateStaticResolutionInvokeVirtualTest.java b/src/test/java/com/android/tools/r8/desugaring/interfacemethods/DefaultInterfaceMethodDesugaringWithPrivateStaticResolutionInvokeVirtualTest.java
index db6f9ef..c8db6fb 100644
--- a/src/test/java/com/android/tools/r8/desugaring/interfacemethods/DefaultInterfaceMethodDesugaringWithPrivateStaticResolutionInvokeVirtualTest.java
+++ b/src/test/java/com/android/tools/r8/desugaring/interfacemethods/DefaultInterfaceMethodDesugaringWithPrivateStaticResolutionInvokeVirtualTest.java
@@ -10,9 +10,9 @@
 import com.android.tools.r8.TestRunResult;
 import com.android.tools.r8.ToolHelper.DexVm;
 import com.android.tools.r8.ToolHelper.DexVm.Version;
-import com.android.tools.r8.utils.internal.BooleanUtils;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.Collection;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/desugaring/interfacemethods/DefaultInterfaceMethodDesugaringWithPrivateStaticResolutionTest.java b/src/test/java/com/android/tools/r8/desugaring/interfacemethods/DefaultInterfaceMethodDesugaringWithPrivateStaticResolutionTest.java
index 49d8b4b..3b97b2b 100644
--- a/src/test/java/com/android/tools/r8/desugaring/interfacemethods/DefaultInterfaceMethodDesugaringWithPrivateStaticResolutionTest.java
+++ b/src/test/java/com/android/tools/r8/desugaring/interfacemethods/DefaultInterfaceMethodDesugaringWithPrivateStaticResolutionTest.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/desugaring/interfacemethods/DefaultInterfaceMethodDesugaringWithPublicStaticResolutionInvokeVirtualTest.java b/src/test/java/com/android/tools/r8/desugaring/interfacemethods/DefaultInterfaceMethodDesugaringWithPublicStaticResolutionInvokeVirtualTest.java
index b6c52d3..be8d8bd 100644
--- a/src/test/java/com/android/tools/r8/desugaring/interfacemethods/DefaultInterfaceMethodDesugaringWithPublicStaticResolutionInvokeVirtualTest.java
+++ b/src/test/java/com/android/tools/r8/desugaring/interfacemethods/DefaultInterfaceMethodDesugaringWithPublicStaticResolutionInvokeVirtualTest.java
@@ -9,9 +9,9 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestRunResult;
 import com.android.tools.r8.ToolHelper.DexVm.Version;
-import com.android.tools.r8.utils.internal.BooleanUtils;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.Collection;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/desugaring/interfacemethods/DefaultInterfaceMethodDesugaringWithPublicStaticResolutionOnClassTest.java b/src/test/java/com/android/tools/r8/desugaring/interfacemethods/DefaultInterfaceMethodDesugaringWithPublicStaticResolutionOnClassTest.java
index 01dd9df..5c0f343 100644
--- a/src/test/java/com/android/tools/r8/desugaring/interfacemethods/DefaultInterfaceMethodDesugaringWithPublicStaticResolutionOnClassTest.java
+++ b/src/test/java/com/android/tools/r8/desugaring/interfacemethods/DefaultInterfaceMethodDesugaringWithPublicStaticResolutionOnClassTest.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ToolHelper.DexVm.Version;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.Collection;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/desugaring/interfacemethods/DefaultInterfaceMethodDesugaringWithPublicStaticResolutionTest.java b/src/test/java/com/android/tools/r8/desugaring/interfacemethods/DefaultInterfaceMethodDesugaringWithPublicStaticResolutionTest.java
index 2ebb188..5f5955c 100644
--- a/src/test/java/com/android/tools/r8/desugaring/interfacemethods/DefaultInterfaceMethodDesugaringWithPublicStaticResolutionTest.java
+++ b/src/test/java/com/android/tools/r8/desugaring/interfacemethods/DefaultInterfaceMethodDesugaringWithPublicStaticResolutionTest.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.Collection;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/desugaring/interfacemethods/DefaultMethodInvokeSuperOnDefaultLibraryMethodTest.java b/src/test/java/com/android/tools/r8/desugaring/interfacemethods/DefaultMethodInvokeSuperOnDefaultLibraryMethodTest.java
index 7611545..1b238f9 100644
--- a/src/test/java/com/android/tools/r8/desugaring/interfacemethods/DefaultMethodInvokeSuperOnDefaultLibraryMethodTest.java
+++ b/src/test/java/com/android/tools/r8/desugaring/interfacemethods/DefaultMethodInvokeSuperOnDefaultLibraryMethodTest.java
@@ -18,7 +18,7 @@
 import com.android.tools.r8.errors.InterfaceDesugarMissingTypeDiagnostic;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.StringDiagnostic;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.ArrayList;
 import java.util.Iterator;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/desugaring/interfacemethods/InterfaceWithClinitAndNoStaticMethodReferencesTest.java b/src/test/java/com/android/tools/r8/desugaring/interfacemethods/InterfaceWithClinitAndNoStaticMethodReferencesTest.java
index 3fee496..36d213c 100644
--- a/src/test/java/com/android/tools/r8/desugaring/interfacemethods/InterfaceWithClinitAndNoStaticMethodReferencesTest.java
+++ b/src/test/java/com/android/tools/r8/desugaring/interfacemethods/InterfaceWithClinitAndNoStaticMethodReferencesTest.java
@@ -6,7 +6,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/desugaring/interfacemethods/InterfaceWithClinitAndNoStaticMethodsTest.java b/src/test/java/com/android/tools/r8/desugaring/interfacemethods/InterfaceWithClinitAndNoStaticMethodsTest.java
index 26adc44..8ac6aed 100644
--- a/src/test/java/com/android/tools/r8/desugaring/interfacemethods/InterfaceWithClinitAndNoStaticMethodsTest.java
+++ b/src/test/java/com/android/tools/r8/desugaring/interfacemethods/InterfaceWithClinitAndNoStaticMethodsTest.java
@@ -6,7 +6,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/desugaring/interfacemethods/InvokeSuperInDefaultInterfaceMethodTest.java b/src/test/java/com/android/tools/r8/desugaring/interfacemethods/InvokeSuperInDefaultInterfaceMethodTest.java
index b80cfb8..520c012 100644
--- a/src/test/java/com/android/tools/r8/desugaring/interfacemethods/InvokeSuperInDefaultInterfaceMethodTest.java
+++ b/src/test/java/com/android/tools/r8/desugaring/interfacemethods/InvokeSuperInDefaultInterfaceMethodTest.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/desugaring/interfacemethods/InvokeSuperInDefaultInterfaceMethodToNonImmediateInterfaceTest.java b/src/test/java/com/android/tools/r8/desugaring/interfacemethods/InvokeSuperInDefaultInterfaceMethodToNonImmediateInterfaceTest.java
index 2933dd7..3822832 100644
--- a/src/test/java/com/android/tools/r8/desugaring/interfacemethods/InvokeSuperInDefaultInterfaceMethodToNonImmediateInterfaceTest.java
+++ b/src/test/java/com/android/tools/r8/desugaring/interfacemethods/InvokeSuperInDefaultInterfaceMethodToNonImmediateInterfaceTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/desugaring/interfacemethods/MethodParametersTest.java b/src/test/java/com/android/tools/r8/desugaring/interfacemethods/MethodParametersTest.java
index 9109d83..0166e6e 100644
--- a/src/test/java/com/android/tools/r8/desugaring/interfacemethods/MethodParametersTest.java
+++ b/src/test/java/com/android/tools/r8/desugaring/interfacemethods/MethodParametersTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.ToolHelper.DexVm.Version;
 import com.android.tools.r8.desugaring.interfacemethods.methodparameters.I;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.SupplierUtils;
 import java.nio.file.Path;
 import java.util.function.Supplier;
diff --git a/src/test/java/com/android/tools/r8/desugaring/interfacemethods/ReturnTest.java b/src/test/java/com/android/tools/r8/desugaring/interfacemethods/ReturnTest.java
index ffda09e..0c1a19a 100644
--- a/src/test/java/com/android/tools/r8/desugaring/interfacemethods/ReturnTest.java
+++ b/src/test/java/com/android/tools/r8/desugaring/interfacemethods/ReturnTest.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/desugaring/interfacemethods/TrapeziumTest.java b/src/test/java/com/android/tools/r8/desugaring/interfacemethods/TrapeziumTest.java
index ee0308f..6f9c402 100644
--- a/src/test/java/com/android/tools/r8/desugaring/interfacemethods/TrapeziumTest.java
+++ b/src/test/java/com/android/tools/r8/desugaring/interfacemethods/TrapeziumTest.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/desugaring/lambdanames/PackageDependentLambdaNamesTest.java b/src/test/java/com/android/tools/r8/desugaring/lambdanames/PackageDependentLambdaNamesTest.java
index d1d228e..91771f8 100644
--- a/src/test/java/com/android/tools/r8/desugaring/lambdanames/PackageDependentLambdaNamesTest.java
+++ b/src/test/java/com/android/tools/r8/desugaring/lambdanames/PackageDependentLambdaNamesTest.java
@@ -10,9 +10,9 @@
 import com.android.tools.r8.TestBuilder;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.transformers.ClassFileTransformer;
-import com.android.tools.r8.utils.internal.BooleanUtils;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/dex/whitespaceinidentifiers/WhiteSpaceInIdentifiersTest.java b/src/test/java/com/android/tools/r8/dex/whitespaceinidentifiers/WhiteSpaceInIdentifiersTest.java
index dc07705..d51c455 100644
--- a/src/test/java/com/android/tools/r8/dex/whitespaceinidentifiers/WhiteSpaceInIdentifiersTest.java
+++ b/src/test/java/com/android/tools/r8/dex/whitespaceinidentifiers/WhiteSpaceInIdentifiersTest.java
@@ -26,7 +26,7 @@
 import com.android.tools.r8.transformers.ClassFileTransformer.MethodPredicate;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.DexVersion;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.concurrent.ExecutionException;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/dexfilemerger/NonAsciiClassNameChecksumTest.java b/src/test/java/com/android/tools/r8/dexfilemerger/NonAsciiClassNameChecksumTest.java
index 2c926c7..b6a20da 100644
--- a/src/test/java/com/android/tools/r8/dexfilemerger/NonAsciiClassNameChecksumTest.java
+++ b/src/test/java/com/android/tools/r8/dexfilemerger/NonAsciiClassNameChecksumTest.java
@@ -11,9 +11,9 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.nio.file.Path;
 import org.junit.Test;
@@ -97,4 +97,4 @@
       System.out.println("Hello å");
     }
   }
-}
\ No newline at end of file
+}
diff --git a/src/test/java/com/android/tools/r8/dexsplitter/DexSplitterFieldTypeStrengtheningTest.java b/src/test/java/com/android/tools/r8/dexsplitter/DexSplitterFieldTypeStrengtheningTest.java
index e1deccc..543b555 100644
--- a/src/test/java/com/android/tools/r8/dexsplitter/DexSplitterFieldTypeStrengtheningTest.java
+++ b/src/test/java/com/android/tools/r8/dexsplitter/DexSplitterFieldTypeStrengtheningTest.java
@@ -13,9 +13,9 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ToolHelper.ProcessResult;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.FieldSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableSet;
 import java.io.IOException;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/dexsplitter/DexSplitterInlineRegression.java b/src/test/java/com/android/tools/r8/dexsplitter/DexSplitterInlineRegression.java
index 3462d9c..dc9963b 100644
--- a/src/test/java/com/android/tools/r8/dexsplitter/DexSplitterInlineRegression.java
+++ b/src/test/java/com/android/tools/r8/dexsplitter/DexSplitterInlineRegression.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.ThrowableConsumer;
 import com.android.tools.r8.ToolHelper.ProcessResult;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableSet;
 import java.io.IOException;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/dexsplitter/DexSplitterMemberValuePropagationRegression.java b/src/test/java/com/android/tools/r8/dexsplitter/DexSplitterMemberValuePropagationRegression.java
index 6b71354..fcb0b86 100644
--- a/src/test/java/com/android/tools/r8/dexsplitter/DexSplitterMemberValuePropagationRegression.java
+++ b/src/test/java/com/android/tools/r8/dexsplitter/DexSplitterMemberValuePropagationRegression.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.ThrowableConsumer;
 import com.android.tools.r8.ToolHelper.ProcessResult;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableSet;
 import java.io.IOException;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/dexsplitter/DexSplitterMergeRegression.java b/src/test/java/com/android/tools/r8/dexsplitter/DexSplitterMergeRegression.java
index 02d7220..a0b7dd6 100644
--- a/src/test/java/com/android/tools/r8/dexsplitter/DexSplitterMergeRegression.java
+++ b/src/test/java/com/android/tools/r8/dexsplitter/DexSplitterMergeRegression.java
@@ -16,7 +16,7 @@
 import com.android.tools.r8.ThrowableConsumer;
 import com.android.tools.r8.ToolHelper.ProcessResult;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableSet;
 import java.io.IOException;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/dexsplitter/R8FeatureSplitServiceLoaderTest.java b/src/test/java/com/android/tools/r8/dexsplitter/R8FeatureSplitServiceLoaderTest.java
index b70f0ae..5fa6452 100644
--- a/src/test/java/com/android/tools/r8/dexsplitter/R8FeatureSplitServiceLoaderTest.java
+++ b/src/test/java/com/android/tools/r8/dexsplitter/R8FeatureSplitServiceLoaderTest.java
@@ -20,7 +20,7 @@
 import com.android.tools.r8.ToolHelper.DexVm.Version;
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.collections.Pair;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/dexsplitter/R8FeatureSplitTest.java b/src/test/java/com/android/tools/r8/dexsplitter/R8FeatureSplitTest.java
index b7e62e6..cbd177d 100644
--- a/src/test/java/com/android/tools/r8/dexsplitter/R8FeatureSplitTest.java
+++ b/src/test/java/com/android/tools/r8/dexsplitter/R8FeatureSplitTest.java
@@ -22,8 +22,8 @@
 import com.android.tools.r8.dex.Marker;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.ExtractMarkerUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.collections.Pair;
 import com.google.common.collect.ImmutableList;
 import com.google.common.io.ByteStreams;
diff --git a/src/test/java/com/android/tools/r8/dexsplitter/R8SplitterInlineToFeature.java b/src/test/java/com/android/tools/r8/dexsplitter/R8SplitterInlineToFeature.java
index 2f118d7..37750a3 100644
--- a/src/test/java/com/android/tools/r8/dexsplitter/R8SplitterInlineToFeature.java
+++ b/src/test/java/com/android/tools/r8/dexsplitter/R8SplitterInlineToFeature.java
@@ -17,8 +17,8 @@
 import com.android.tools.r8.ThrowableConsumer;
 import com.android.tools.r8.ToolHelper.ProcessResult;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableSet;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/dexsplitter/SyntheticDistributionTest.java b/src/test/java/com/android/tools/r8/dexsplitter/SyntheticDistributionTest.java
index bc46b80..df2302d 100644
--- a/src/test/java/com/android/tools/r8/dexsplitter/SyntheticDistributionTest.java
+++ b/src/test/java/com/android/tools/r8/dexsplitter/SyntheticDistributionTest.java
@@ -18,8 +18,8 @@
 import com.android.tools.r8.apimodel.ApiModelingTestHelper;
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.FoundClassSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableSet;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/diagnostics/ErrorDuringIrConversionTest.java b/src/test/java/com/android/tools/r8/diagnostics/ErrorDuringIrConversionTest.java
index 07d4b2f3..a44c8ee 100644
--- a/src/test/java/com/android/tools/r8/diagnostics/ErrorDuringIrConversionTest.java
+++ b/src/test/java/com/android/tools/r8/diagnostics/ErrorDuringIrConversionTest.java
@@ -23,7 +23,7 @@
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.utils.Reporter;
 import com.android.tools.r8.utils.StringDiagnostic;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.PrintWriter;
 import java.io.StringWriter;
 import java.util.concurrent.atomic.AtomicBoolean;
diff --git a/src/test/java/com/android/tools/r8/diagnostics/ProgramAndLibraryDuplicatesTest.java b/src/test/java/com/android/tools/r8/diagnostics/ProgramAndLibraryDuplicatesTest.java
index e9b75b6..a8e4624 100644
--- a/src/test/java/com/android/tools/r8/diagnostics/ProgramAndLibraryDuplicatesTest.java
+++ b/src/test/java/com/android/tools/r8/diagnostics/ProgramAndLibraryDuplicatesTest.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.errors.DuplicateTypeInProgramAndLibraryDiagnostic;
 import com.android.tools.r8.errors.DuplicateTypesDiagnostic;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/dump/CompilerDumpTest.java b/src/test/java/com/android/tools/r8/dump/CompilerDumpTest.java
index cfa3bdc..100c645 100644
--- a/src/test/java/com/android/tools/r8/dump/CompilerDumpTest.java
+++ b/src/test/java/com/android/tools/r8/dump/CompilerDumpTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.internal.CompilationTestBase;
 import com.android.tools.r8.utils.DumpInputFlags;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.Lists;
 import java.nio.file.Files;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/dump/DumpInputsD8Test.java b/src/test/java/com/android/tools/r8/dump/DumpInputsD8Test.java
index 54b75c2..1ac3416 100644
--- a/src/test/java/com/android/tools/r8/dump/DumpInputsD8Test.java
+++ b/src/test/java/com/android/tools/r8/dump/DumpInputsD8Test.java
@@ -15,8 +15,8 @@
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.utils.DescriptorUtils;
 import com.android.tools.r8.utils.DumpInputFlags;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.ZipUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.nio.file.Files;
diff --git a/src/test/java/com/android/tools/r8/dump/DumpMainDexInputsTest.java b/src/test/java/com/android/tools/r8/dump/DumpMainDexInputsTest.java
index ebbb9aa..8bf3481 100644
--- a/src/test/java/com/android/tools/r8/dump/DumpMainDexInputsTest.java
+++ b/src/test/java/com/android/tools/r8/dump/DumpMainDexInputsTest.java
@@ -15,9 +15,9 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.DumpInputFlags;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.ZipUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/enumunboxing/EnumUnboxingReturnNullTest.java b/src/test/java/com/android/tools/r8/enumunboxing/EnumUnboxingReturnNullTest.java
index c1f38cf..bb0d2c0 100644
--- a/src/test/java/com/android/tools/r8/enumunboxing/EnumUnboxingReturnNullTest.java
+++ b/src/test/java/com/android/tools/r8/enumunboxing/EnumUnboxingReturnNullTest.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.NeverClassInline;
 import com.android.tools.r8.NeverInline;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/enumunboxing/GenerateEnumUnboxingMethods.java b/src/test/java/com/android/tools/r8/enumunboxing/GenerateEnumUnboxingMethods.java
index cfce913..86b1b06 100644
--- a/src/test/java/com/android/tools/r8/enumunboxing/GenerateEnumUnboxingMethods.java
+++ b/src/test/java/com/android/tools/r8/enumunboxing/GenerateEnumUnboxingMethods.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.ToolHelper.TestDataSourceSet;
 import com.android.tools.r8.cfmethodgeneration.MethodGenerationBase;
 import com.android.tools.r8.graph.DexType;
-import com.android.tools.r8.utils.FileUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.charset.StandardCharsets;
 import java.util.ArrayList;
diff --git a/src/test/java/com/android/tools/r8/enumunboxing/LargeEnumUnboxingTest.java b/src/test/java/com/android/tools/r8/enumunboxing/LargeEnumUnboxingTest.java
index 1624d46..c42be59 100644
--- a/src/test/java/com/android/tools/r8/enumunboxing/LargeEnumUnboxingTest.java
+++ b/src/test/java/com/android/tools/r8/enumunboxing/LargeEnumUnboxingTest.java
@@ -6,7 +6,7 @@
 
 import com.android.tools.r8.NeverClassInline;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/enumunboxing/enummerging/AbstractMethodErrorEnumMergingTest.java b/src/test/java/com/android/tools/r8/enumunboxing/enummerging/AbstractMethodErrorEnumMergingTest.java
index b11d6de..a194d093 100644
--- a/src/test/java/com/android/tools/r8/enumunboxing/enummerging/AbstractMethodErrorEnumMergingTest.java
+++ b/src/test/java/com/android/tools/r8/enumunboxing/enummerging/AbstractMethodErrorEnumMergingTest.java
@@ -9,8 +9,8 @@
 import com.android.tools.r8.NeverInline;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.enumunboxing.EnumUnboxingTestBase;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.EnumUnboxingInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.util.ArrayList;
diff --git a/src/test/java/com/android/tools/r8/enumunboxing/enummerging/SuperEnumMergingTest.java b/src/test/java/com/android/tools/r8/enumunboxing/enummerging/SuperEnumMergingTest.java
index 1bb41ca..c05c1d2 100644
--- a/src/test/java/com/android/tools/r8/enumunboxing/enummerging/SuperEnumMergingTest.java
+++ b/src/test/java/com/android/tools/r8/enumunboxing/enummerging/SuperEnumMergingTest.java
@@ -6,7 +6,7 @@
 import com.android.tools.r8.NeverInline;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.enumunboxing.EnumUnboxingTestBase;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/enumunboxing/enummerging/SuperToStringEnumMergingTest.java b/src/test/java/com/android/tools/r8/enumunboxing/enummerging/SuperToStringEnumMergingTest.java
index 7d7fbfe..c7f39d1 100644
--- a/src/test/java/com/android/tools/r8/enumunboxing/enummerging/SuperToStringEnumMergingTest.java
+++ b/src/test/java/com/android/tools/r8/enumunboxing/enummerging/SuperToStringEnumMergingTest.java
@@ -6,7 +6,7 @@
 import com.android.tools.r8.NeverInline;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.enumunboxing.EnumUnboxingTestBase;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/examples/abstractmethodremoval/AbstractMethodRemovalTestRunner.java b/src/test/java/com/android/tools/r8/examples/abstractmethodremoval/AbstractMethodRemovalTestRunner.java
index 78e971c..cd71ea0 100644
--- a/src/test/java/com/android/tools/r8/examples/abstractmethodremoval/AbstractMethodRemovalTestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/abstractmethodremoval/AbstractMethodRemovalTestRunner.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.examples.abstractmethodremoval.a.Public;
 import com.android.tools.r8.examples.abstractmethodremoval.b.Impl1;
 import com.android.tools.r8.examples.abstractmethodremoval.b.Impl2;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/examples/arrayaccess/ArrayAccessTestRunner.java b/src/test/java/com/android/tools/r8/examples/arrayaccess/ArrayAccessTestRunner.java
index cc33ad3..4c6feb6 100644
--- a/src/test/java/com/android/tools/r8/examples/arrayaccess/ArrayAccessTestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/arrayaccess/ArrayAccessTestRunner.java
@@ -4,10 +4,8 @@
 package com.android.tools.r8.examples.arrayaccess;
 
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.examples.ExamplesTestBase;
-import com.android.tools.r8.utils.StringUtils;
-import org.junit.Test;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
 
diff --git a/src/test/java/com/android/tools/r8/examples/barray/BArrayTestRunner.java b/src/test/java/com/android/tools/r8/examples/barray/BArrayTestRunner.java
index 7ebbf7d..dac9e72 100644
--- a/src/test/java/com/android/tools/r8/examples/barray/BArrayTestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/barray/BArrayTestRunner.java
@@ -4,10 +4,8 @@
 package com.android.tools.r8.examples.barray;
 
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.examples.ExamplesTestBase;
-import com.android.tools.r8.utils.StringUtils;
-import org.junit.Test;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
 
diff --git a/src/test/java/com/android/tools/r8/examples/bridge/BridgeMethodTestRunner.java b/src/test/java/com/android/tools/r8/examples/bridge/BridgeMethodTestRunner.java
index 18b0431..c184fdf 100644
--- a/src/test/java/com/android/tools/r8/examples/bridge/BridgeMethodTestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/bridge/BridgeMethodTestRunner.java
@@ -4,12 +4,10 @@
 package com.android.tools.r8.examples.bridge;
 
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.examples.ExamplesTestBase;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
-import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
 
diff --git a/src/test/java/com/android/tools/r8/examples/catchhandleroverlap/CatchHandlerOverlapTestRunner.java b/src/test/java/com/android/tools/r8/examples/catchhandleroverlap/CatchHandlerOverlapTestRunner.java
index 33bd829..4f86658 100644
--- a/src/test/java/com/android/tools/r8/examples/catchhandleroverlap/CatchHandlerOverlapTestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/catchhandleroverlap/CatchHandlerOverlapTestRunner.java
@@ -4,10 +4,8 @@
 package com.android.tools.r8.examples.catchhandleroverlap;
 
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.examples.ExamplesTestBase;
-import com.android.tools.r8.utils.StringUtils;
-import org.junit.Test;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
 
diff --git a/src/test/java/com/android/tools/r8/examples/controlflow/ControlFlowTestRunner.java b/src/test/java/com/android/tools/r8/examples/controlflow/ControlFlowTestRunner.java
index db1d31e..c52501b 100644
--- a/src/test/java/com/android/tools/r8/examples/controlflow/ControlFlowTestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/controlflow/ControlFlowTestRunner.java
@@ -4,10 +4,8 @@
 package com.android.tools.r8.examples.controlflow;
 
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.examples.ExamplesTestBase;
-import com.android.tools.r8.utils.StringUtils;
-import org.junit.Test;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
 
diff --git a/src/test/java/com/android/tools/r8/examples/conversions/ConversionsTestRunner.java b/src/test/java/com/android/tools/r8/examples/conversions/ConversionsTestRunner.java
index 1cffe25..29a44e1 100644
--- a/src/test/java/com/android/tools/r8/examples/conversions/ConversionsTestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/conversions/ConversionsTestRunner.java
@@ -4,10 +4,8 @@
 package com.android.tools.r8.examples.conversions;
 
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.examples.ExamplesTestBase;
-import com.android.tools.r8.utils.StringUtils;
-import org.junit.Test;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
 
diff --git a/src/test/java/com/android/tools/r8/examples/cse/CommonSubexpressionEliminationTestRunner.java b/src/test/java/com/android/tools/r8/examples/cse/CommonSubexpressionEliminationTestRunner.java
index 4723353..54baaae 100644
--- a/src/test/java/com/android/tools/r8/examples/cse/CommonSubexpressionEliminationTestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/cse/CommonSubexpressionEliminationTestRunner.java
@@ -4,10 +4,8 @@
 package com.android.tools.r8.examples.cse;
 
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.examples.ExamplesTestBase;
-import com.android.tools.r8.utils.StringUtils;
-import org.junit.Test;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
 
diff --git a/src/test/java/com/android/tools/r8/examples/enclosingmethod/EnclosingMethodTestRunner.java b/src/test/java/com/android/tools/r8/examples/enclosingmethod/EnclosingMethodTestRunner.java
index 69f6096..e657612 100644
--- a/src/test/java/com/android/tools/r8/examples/enclosingmethod/EnclosingMethodTestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/enclosingmethod/EnclosingMethodTestRunner.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.ToolHelper.DexVm.Version;
 import com.android.tools.r8.examples.ExamplesTestBase;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Ignore;
diff --git a/src/test/java/com/android/tools/r8/examples/filledarray/FilledArrayTestRunner.java b/src/test/java/com/android/tools/r8/examples/filledarray/FilledArrayTestRunner.java
index 3481991..4274371 100644
--- a/src/test/java/com/android/tools/r8/examples/filledarray/FilledArrayTestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/filledarray/FilledArrayTestRunner.java
@@ -4,10 +4,8 @@
 package com.android.tools.r8.examples.filledarray;
 
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.examples.ExamplesTestBase;
-import com.android.tools.r8.utils.StringUtils;
-import org.junit.Test;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
 
diff --git a/src/test/java/com/android/tools/r8/examples/floating_point_annotations/FloatingPointValuedAnnotationTestRunner.java b/src/test/java/com/android/tools/r8/examples/floating_point_annotations/FloatingPointValuedAnnotationTestRunner.java
index a848d5a..b2f1cc8 100644
--- a/src/test/java/com/android/tools/r8/examples/floating_point_annotations/FloatingPointValuedAnnotationTestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/floating_point_annotations/FloatingPointValuedAnnotationTestRunner.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.ToolHelper.DexVm.Version;
 import com.android.tools.r8.examples.ExamplesTestBase;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/examples/hello/HelloTestRunner.java b/src/test/java/com/android/tools/r8/examples/hello/HelloTestRunner.java
index 2cf9c6a..447dd3f 100644
--- a/src/test/java/com/android/tools/r8/examples/hello/HelloTestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/hello/HelloTestRunner.java
@@ -4,10 +4,8 @@
 package com.android.tools.r8.examples.hello;
 
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.examples.ExamplesTestBase;
-import com.android.tools.r8.utils.StringUtils;
-import org.junit.Test;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
 
diff --git a/src/test/java/com/android/tools/r8/examples/ifstatements/IfStatementsTestRunner.java b/src/test/java/com/android/tools/r8/examples/ifstatements/IfStatementsTestRunner.java
index 668aaa6..0bd41e2 100644
--- a/src/test/java/com/android/tools/r8/examples/ifstatements/IfStatementsTestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/ifstatements/IfStatementsTestRunner.java
@@ -5,7 +5,7 @@
 
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.examples.ExamplesTestBase;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
 
diff --git a/src/test/java/com/android/tools/r8/examples/instanceofstring/InstanceOfStringTestRunner.java b/src/test/java/com/android/tools/r8/examples/instanceofstring/InstanceOfStringTestRunner.java
index 2cfe7e9..a72d986 100644
--- a/src/test/java/com/android/tools/r8/examples/instanceofstring/InstanceOfStringTestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/instanceofstring/InstanceOfStringTestRunner.java
@@ -4,10 +4,8 @@
 package com.android.tools.r8.examples.instanceofstring;
 
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.examples.ExamplesTestBase;
-import com.android.tools.r8.utils.StringUtils;
-import org.junit.Test;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
 
diff --git a/src/test/java/com/android/tools/r8/examples/instancevariable/InstanceVariableTestRunner.java b/src/test/java/com/android/tools/r8/examples/instancevariable/InstanceVariableTestRunner.java
index 6f05e04..b5ab52c 100644
--- a/src/test/java/com/android/tools/r8/examples/instancevariable/InstanceVariableTestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/instancevariable/InstanceVariableTestRunner.java
@@ -4,10 +4,8 @@
 package com.android.tools.r8.examples.instancevariable;
 
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.examples.ExamplesTestBase;
-import com.android.tools.r8.utils.StringUtils;
-import org.junit.Test;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
 
diff --git a/src/test/java/com/android/tools/r8/examples/invoke/InvokeTestRunner.java b/src/test/java/com/android/tools/r8/examples/invoke/InvokeTestRunner.java
index 5a6d94e..9ae5e65 100644
--- a/src/test/java/com/android/tools/r8/examples/invoke/InvokeTestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/invoke/InvokeTestRunner.java
@@ -5,7 +5,7 @@
 
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.examples.ExamplesTestBase;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/examples/jumbostring/JumboStringTestRunner.java b/src/test/java/com/android/tools/r8/examples/jumbostring/JumboStringTestRunner.java
index 2a007fa..5857fda 100644
--- a/src/test/java/com/android/tools/r8/examples/jumbostring/JumboStringTestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/jumbostring/JumboStringTestRunner.java
@@ -6,7 +6,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.examples.ExamplesTestBase;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.io.PrintStream;
diff --git a/src/test/java/com/android/tools/r8/examples/loadconst/LoadConstTestRunner.java b/src/test/java/com/android/tools/r8/examples/loadconst/LoadConstTestRunner.java
index 9604698..e3b962e 100644
--- a/src/test/java/com/android/tools/r8/examples/loadconst/LoadConstTestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/loadconst/LoadConstTestRunner.java
@@ -4,10 +4,8 @@
 package com.android.tools.r8.examples.loadconst;
 
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.examples.ExamplesTestBase;
-import com.android.tools.r8.utils.StringUtils;
-import org.junit.Test;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
 
diff --git a/src/test/java/com/android/tools/r8/examples/loadconst/UdpServerTestRunner.java b/src/test/java/com/android/tools/r8/examples/loadconst/UdpServerTestRunner.java
index 0798230..3f4d521 100644
--- a/src/test/java/com/android/tools/r8/examples/loadconst/UdpServerTestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/loadconst/UdpServerTestRunner.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.examples.ExamplesTestBase;
 import com.android.tools.r8.examples.loop.UdpServer;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Ignore;
diff --git a/src/test/java/com/android/tools/r8/examples/nestedtrycatches/NestedTryCatchesTestRunner.java b/src/test/java/com/android/tools/r8/examples/nestedtrycatches/NestedTryCatchesTestRunner.java
index 0c02874..b5c9db2 100644
--- a/src/test/java/com/android/tools/r8/examples/nestedtrycatches/NestedTryCatchesTestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/nestedtrycatches/NestedTryCatchesTestRunner.java
@@ -4,10 +4,8 @@
 package com.android.tools.r8.examples.nestedtrycatches;
 
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.examples.ExamplesTestBase;
-import com.android.tools.r8.utils.StringUtils;
-import org.junit.Test;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
 
diff --git a/src/test/java/com/android/tools/r8/examples/regalloc/RegAllocTestRunner.java b/src/test/java/com/android/tools/r8/examples/regalloc/RegAllocTestRunner.java
index cdb8b23..c061f0a 100644
--- a/src/test/java/com/android/tools/r8/examples/regalloc/RegAllocTestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/regalloc/RegAllocTestRunner.java
@@ -4,13 +4,11 @@
 package com.android.tools.r8.examples.regalloc;
 
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.examples.ExamplesTestBase;
 import com.android.tools.r8.examples.regalloc.RegAlloc.BoxedInteger;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
-import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
 
diff --git a/src/test/java/com/android/tools/r8/examples/regress/RegressTestRunner.java b/src/test/java/com/android/tools/r8/examples/regress/RegressTestRunner.java
index 41b952a..481ddb7 100644
--- a/src/test/java/com/android/tools/r8/examples/regress/RegressTestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/regress/RegressTestRunner.java
@@ -4,10 +4,8 @@
 package com.android.tools.r8.examples.regress;
 
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.examples.ExamplesTestBase;
-import com.android.tools.r8.utils.StringUtils;
-import org.junit.Test;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
 
diff --git a/src/test/java/com/android/tools/r8/examples/regress2/Regress2TestRunner.java b/src/test/java/com/android/tools/r8/examples/regress2/Regress2TestRunner.java
index a276f78..73c027c 100644
--- a/src/test/java/com/android/tools/r8/examples/regress2/Regress2TestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/regress2/Regress2TestRunner.java
@@ -4,12 +4,10 @@
 package com.android.tools.r8.examples.regress2;
 
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.examples.ExamplesTestBase;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
-import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
 
diff --git a/src/test/java/com/android/tools/r8/examples/regress_110373181/Regress110373181TestRunner.java b/src/test/java/com/android/tools/r8/examples/regress_110373181/Regress110373181TestRunner.java
index d347c31..ea6f1ac 100644
--- a/src/test/java/com/android/tools/r8/examples/regress_110373181/Regress110373181TestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/regress_110373181/Regress110373181TestRunner.java
@@ -5,7 +5,7 @@
 
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.examples.ExamplesTestBase;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/examples/regress_37658666/Regress37658666TestRunner.java b/src/test/java/com/android/tools/r8/examples/regress_37658666/Regress37658666TestRunner.java
index 3fdfb53..92675bc 100644
--- a/src/test/java/com/android/tools/r8/examples/regress_37658666/Regress37658666TestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/regress_37658666/Regress37658666TestRunner.java
@@ -4,12 +4,10 @@
 package com.android.tools.r8.examples.regress_37658666;
 
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.examples.ExamplesTestBase;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
-import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
 
diff --git a/src/test/java/com/android/tools/r8/examples/regress_37726195/Regress37726195TestRunner.java b/src/test/java/com/android/tools/r8/examples/regress_37726195/Regress37726195TestRunner.java
index 4c8f25c..1881cf7 100644
--- a/src/test/java/com/android/tools/r8/examples/regress_37726195/Regress37726195TestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/regress_37726195/Regress37726195TestRunner.java
@@ -4,10 +4,8 @@
 package com.android.tools.r8.examples.regress_37726195;
 
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.examples.ExamplesTestBase;
-import com.android.tools.r8.utils.StringUtils;
-import org.junit.Test;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
 
diff --git a/src/test/java/com/android/tools/r8/examples/regress_37875803/Regress37875803TestRunner.java b/src/test/java/com/android/tools/r8/examples/regress_37875803/Regress37875803TestRunner.java
index b695cb9..b5ad597 100644
--- a/src/test/java/com/android/tools/r8/examples/regress_37875803/Regress37875803TestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/regress_37875803/Regress37875803TestRunner.java
@@ -4,10 +4,8 @@
 package com.android.tools.r8.examples.regress_37875803;
 
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.examples.ExamplesTestBase;
-import com.android.tools.r8.utils.StringUtils;
-import org.junit.Test;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
 
diff --git a/src/test/java/com/android/tools/r8/examples/regress_37955340/Regress37955340TestRunner.java b/src/test/java/com/android/tools/r8/examples/regress_37955340/Regress37955340TestRunner.java
index 8b8d01a..9d75807 100644
--- a/src/test/java/com/android/tools/r8/examples/regress_37955340/Regress37955340TestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/regress_37955340/Regress37955340TestRunner.java
@@ -4,12 +4,10 @@
 package com.android.tools.r8.examples.regress_37955340;
 
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.examples.ExamplesTestBase;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
-import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
 
diff --git a/src/test/java/com/android/tools/r8/examples/regress_62300145/Regress62300145TestRunner.java b/src/test/java/com/android/tools/r8/examples/regress_62300145/Regress62300145TestRunner.java
index ddac70e..65b4931 100644
--- a/src/test/java/com/android/tools/r8/examples/regress_62300145/Regress62300145TestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/regress_62300145/Regress62300145TestRunner.java
@@ -5,7 +5,7 @@
 
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.examples.ExamplesTestBase;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/examples/regress_64881691/Regress64881691TestRunner.java b/src/test/java/com/android/tools/r8/examples/regress_64881691/Regress64881691TestRunner.java
index fb8b58c..44e9fb7 100644
--- a/src/test/java/com/android/tools/r8/examples/regress_64881691/Regress64881691TestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/regress_64881691/Regress64881691TestRunner.java
@@ -5,7 +5,7 @@
 
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.examples.ExamplesTestBase;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/examples/regress_65104300/Regress65104300TestRunner.java b/src/test/java/com/android/tools/r8/examples/regress_65104300/Regress65104300TestRunner.java
index 3c9605e..45fd2dc 100644
--- a/src/test/java/com/android/tools/r8/examples/regress_65104300/Regress65104300TestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/regress_65104300/Regress65104300TestRunner.java
@@ -4,10 +4,8 @@
 package com.android.tools.r8.examples.regress_65104300;
 
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.examples.ExamplesTestBase;
-import com.android.tools.r8.utils.StringUtils;
-import org.junit.Test;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
 
diff --git a/src/test/java/com/android/tools/r8/examples/regress_70703087/Regress70703087TestRunner.java b/src/test/java/com/android/tools/r8/examples/regress_70703087/Regress70703087TestRunner.java
index 06272b0..4164f15 100644
--- a/src/test/java/com/android/tools/r8/examples/regress_70703087/Regress70703087TestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/regress_70703087/Regress70703087TestRunner.java
@@ -5,7 +5,7 @@
 
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.examples.ExamplesTestBase;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/examples/regress_70736958/Regress70736958TestRunner.java b/src/test/java/com/android/tools/r8/examples/regress_70736958/Regress70736958TestRunner.java
index 0cbff50..850ba9e 100644
--- a/src/test/java/com/android/tools/r8/examples/regress_70736958/Regress70736958TestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/regress_70736958/Regress70736958TestRunner.java
@@ -5,7 +5,7 @@
 
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.examples.ExamplesTestBase;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/examples/regress_70737019/Regress70737019TestRunner.java b/src/test/java/com/android/tools/r8/examples/regress_70737019/Regress70737019TestRunner.java
index 70791f2..f93efca 100644
--- a/src/test/java/com/android/tools/r8/examples/regress_70737019/Regress70737019TestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/regress_70737019/Regress70737019TestRunner.java
@@ -4,12 +4,10 @@
 package com.android.tools.r8.examples.regress_70737019;
 
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.examples.ExamplesTestBase;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
-import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
 
diff --git a/src/test/java/com/android/tools/r8/examples/regress_72361252/Regress72361252TestRunner.java b/src/test/java/com/android/tools/r8/examples/regress_72361252/Regress72361252TestRunner.java
index c37d82e..f5f8a2d 100644
--- a/src/test/java/com/android/tools/r8/examples/regress_72361252/Regress72361252TestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/regress_72361252/Regress72361252TestRunner.java
@@ -4,12 +4,10 @@
 package com.android.tools.r8.examples.regress_72361252;
 
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.examples.ExamplesTestBase;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
-import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
 
diff --git a/src/test/java/com/android/tools/r8/examples/staticfield/StaticFieldTestRunner.java b/src/test/java/com/android/tools/r8/examples/staticfield/StaticFieldTestRunner.java
index 9c19a48..fa511a9 100644
--- a/src/test/java/com/android/tools/r8/examples/staticfield/StaticFieldTestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/staticfield/StaticFieldTestRunner.java
@@ -5,7 +5,7 @@
 
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.examples.ExamplesTestBase;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/examples/stringbuilding/StringBuildingTestRunner.java b/src/test/java/com/android/tools/r8/examples/stringbuilding/StringBuildingTestRunner.java
index 15aa27a..1db1f05 100644
--- a/src/test/java/com/android/tools/r8/examples/stringbuilding/StringBuildingTestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/stringbuilding/StringBuildingTestRunner.java
@@ -4,12 +4,10 @@
 package com.android.tools.r8.examples.stringbuilding;
 
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.examples.ExamplesTestBase;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
-import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
 
diff --git a/src/test/java/com/android/tools/r8/examples/switches/SwitchesTestRunner.java b/src/test/java/com/android/tools/r8/examples/switches/SwitchesTestRunner.java
index 72149a4..5ff303b 100644
--- a/src/test/java/com/android/tools/r8/examples/switches/SwitchesTestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/switches/SwitchesTestRunner.java
@@ -5,7 +5,7 @@
 
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.examples.ExamplesTestBase;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.apache.harmony.jpda.tests.framework.TestErrorException;
 import org.apache.harmony.jpda.tests.framework.jdwp.exceptions.TimeoutException;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/examples/switchmaps/SwitchMapsTestRunner.java b/src/test/java/com/android/tools/r8/examples/switchmaps/SwitchMapsTestRunner.java
index 1591c2a..7cc2a03 100644
--- a/src/test/java/com/android/tools/r8/examples/switchmaps/SwitchMapsTestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/switchmaps/SwitchMapsTestRunner.java
@@ -5,7 +5,7 @@
 
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.examples.ExamplesTestBase;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/examples/sync/SyncTestRunner.java b/src/test/java/com/android/tools/r8/examples/sync/SyncTestRunner.java
index 3353705..7a84891 100644
--- a/src/test/java/com/android/tools/r8/examples/sync/SyncTestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/sync/SyncTestRunner.java
@@ -6,7 +6,7 @@
 
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.examples.ExamplesTestBase;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.ArrayList;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/examples/throwing/ThrowingTestRunner.java b/src/test/java/com/android/tools/r8/examples/throwing/ThrowingTestRunner.java
index 9c9dc96..9406d4d 100644
--- a/src/test/java/com/android/tools/r8/examples/throwing/ThrowingTestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/throwing/ThrowingTestRunner.java
@@ -5,7 +5,7 @@
 
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.examples.ExamplesTestBase;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.apache.harmony.jpda.tests.framework.TestErrorException;
diff --git a/src/test/java/com/android/tools/r8/examples/trycatch/TryCatchTestRunner.java b/src/test/java/com/android/tools/r8/examples/trycatch/TryCatchTestRunner.java
index 87b1ef6..cc1fe84 100644
--- a/src/test/java/com/android/tools/r8/examples/trycatch/TryCatchTestRunner.java
+++ b/src/test/java/com/android/tools/r8/examples/trycatch/TryCatchTestRunner.java
@@ -4,12 +4,10 @@
 package com.android.tools.r8.examples.trycatch;
 
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.examples.ExamplesTestBase;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
-import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
 
diff --git a/src/test/java/com/android/tools/r8/files/ArchiveWithDexTest.java b/src/test/java/com/android/tools/r8/files/ArchiveWithDexTest.java
index a86fc96..230d0f6 100644
--- a/src/test/java/com/android/tools/r8/files/ArchiveWithDexTest.java
+++ b/src/test/java/com/android/tools/r8/files/ArchiveWithDexTest.java
@@ -24,9 +24,9 @@
 import com.android.tools.r8.origin.PathOrigin;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.ArchiveResourceProvider;
-import com.android.tools.r8.utils.internal.BooleanBox;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.ZipUtils;
+import com.android.tools.r8.utils.internal.BooleanBox;
+import com.android.tools.r8.utils.internal.FileUtils;
 import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/graph/InvokeSuperTest.java b/src/test/java/com/android/tools/r8/graph/InvokeSuperTest.java
index 8f54230..54da8c1 100644
--- a/src/test/java/com/android/tools/r8/graph/InvokeSuperTest.java
+++ b/src/test/java/com/android/tools/r8/graph/InvokeSuperTest.java
@@ -18,8 +18,8 @@
 import com.android.tools.r8.ToolHelper.DexVm.Version;
 import com.android.tools.r8.transformers.ClassTransformer;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.UnverifiableCfCodeDiagnostic;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/graph/genericsignature/GenericSignatureSelfReferencingEnclosingConstructorTest.java b/src/test/java/com/android/tools/r8/graph/genericsignature/GenericSignatureSelfReferencingEnclosingConstructorTest.java
index 79c68c2..93d0e58 100644
--- a/src/test/java/com/android/tools/r8/graph/genericsignature/GenericSignatureSelfReferencingEnclosingConstructorTest.java
+++ b/src/test/java/com/android/tools/r8/graph/genericsignature/GenericSignatureSelfReferencingEnclosingConstructorTest.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.references.Reference;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.nio.file.Path;
 import java.util.Iterator;
diff --git a/src/test/java/com/android/tools/r8/graph/genericsignature/GenericSignatureSelfReferencingEnclosingMethodTest.java b/src/test/java/com/android/tools/r8/graph/genericsignature/GenericSignatureSelfReferencingEnclosingMethodTest.java
index 92685d4..3213b81 100644
--- a/src/test/java/com/android/tools/r8/graph/genericsignature/GenericSignatureSelfReferencingEnclosingMethodTest.java
+++ b/src/test/java/com/android/tools/r8/graph/genericsignature/GenericSignatureSelfReferencingEnclosingMethodTest.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.references.Reference;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.nio.file.Path;
 import java.util.Iterator;
diff --git a/src/test/java/com/android/tools/r8/graph/genericsignature/GenericSignatureSelfReferencingInnerClassesTest.java b/src/test/java/com/android/tools/r8/graph/genericsignature/GenericSignatureSelfReferencingInnerClassesTest.java
index d5b3460..b397ab6 100644
--- a/src/test/java/com/android/tools/r8/graph/genericsignature/GenericSignatureSelfReferencingInnerClassesTest.java
+++ b/src/test/java/com/android/tools/r8/graph/genericsignature/GenericSignatureSelfReferencingInnerClassesTest.java
@@ -15,8 +15,8 @@
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.graph.genericsignature.GenericSignatureSelfReferencingInnerClassesTest.A.B;
 import com.android.tools.r8.references.Reference;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.nio.file.Path;
 import java.util.Iterator;
diff --git a/src/test/java/com/android/tools/r8/graph/invokespecial/InvokeSpecialForInvokeVirtualTest.java b/src/test/java/com/android/tools/r8/graph/invokespecial/InvokeSpecialForInvokeVirtualTest.java
index 4d28dba..f7031da 100644
--- a/src/test/java/com/android/tools/r8/graph/invokespecial/InvokeSpecialForInvokeVirtualTest.java
+++ b/src/test/java/com/android/tools/r8/graph/invokespecial/InvokeSpecialForInvokeVirtualTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/graph/invokespecial/InvokeSpecialForNonDeclaredInvokeVirtualTest.java b/src/test/java/com/android/tools/r8/graph/invokespecial/InvokeSpecialForNonDeclaredInvokeVirtualTest.java
index 4ae689a..e559a6c 100644
--- a/src/test/java/com/android/tools/r8/graph/invokespecial/InvokeSpecialForNonDeclaredInvokeVirtualTest.java
+++ b/src/test/java/com/android/tools/r8/graph/invokespecial/InvokeSpecialForNonDeclaredInvokeVirtualTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/graph/invokespecial/InvokeSpecialInterfaceWithBridge2Test.java b/src/test/java/com/android/tools/r8/graph/invokespecial/InvokeSpecialInterfaceWithBridge2Test.java
index f7f75b0..47d37eb 100644
--- a/src/test/java/com/android/tools/r8/graph/invokespecial/InvokeSpecialInterfaceWithBridge2Test.java
+++ b/src/test/java/com/android/tools/r8/graph/invokespecial/InvokeSpecialInterfaceWithBridge2Test.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/graph/invokespecial/InvokeSpecialInterfaceWithBridge3Test.java b/src/test/java/com/android/tools/r8/graph/invokespecial/InvokeSpecialInterfaceWithBridge3Test.java
index f3cc39a..9303fe5 100644
--- a/src/test/java/com/android/tools/r8/graph/invokespecial/InvokeSpecialInterfaceWithBridge3Test.java
+++ b/src/test/java/com/android/tools/r8/graph/invokespecial/InvokeSpecialInterfaceWithBridge3Test.java
@@ -16,7 +16,7 @@
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.ToolHelper.DexVm.Version;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/graph/invokespecial/InvokeSpecialSuperVirtualTest.java b/src/test/java/com/android/tools/r8/graph/invokespecial/InvokeSpecialSuperVirtualTest.java
index e3e14ac..9e43d89 100644
--- a/src/test/java/com/android/tools/r8/graph/invokespecial/InvokeSpecialSuperVirtualTest.java
+++ b/src/test/java/com/android/tools/r8/graph/invokespecial/InvokeSpecialSuperVirtualTest.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/graph/invokespecial/InvokeSpecialToVirtualMethodTest.java b/src/test/java/com/android/tools/r8/graph/invokespecial/InvokeSpecialToVirtualMethodTest.java
index adaf1fb..14535b6 100644
--- a/src/test/java/com/android/tools/r8/graph/invokespecial/InvokeSpecialToVirtualMethodTest.java
+++ b/src/test/java/com/android/tools/r8/graph/invokespecial/InvokeSpecialToVirtualMethodTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ToolHelper.DexVm.Version;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/graph/invokespecial/MultipleInvokeSpecialOnSameClassTest.java b/src/test/java/com/android/tools/r8/graph/invokespecial/MultipleInvokeSpecialOnSameClassTest.java
index 46262f4..76fbeff 100644
--- a/src/test/java/com/android/tools/r8/graph/invokespecial/MultipleInvokeSpecialOnSameClassTest.java
+++ b/src/test/java/com/android/tools/r8/graph/invokespecial/MultipleInvokeSpecialOnSameClassTest.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/gson/GsonDefaultConstructorTest.java b/src/test/java/com/android/tools/r8/gson/GsonDefaultConstructorTest.java
index a8b7939..d9e9284 100644
--- a/src/test/java/com/android/tools/r8/gson/GsonDefaultConstructorTest.java
+++ b/src/test/java/com/android/tools/r8/gson/GsonDefaultConstructorTest.java
@@ -11,10 +11,10 @@
 import com.android.tools.r8.ProguardVersion;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.ToolHelper.DexVm.Version;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.gson.Gson;
 import com.google.gson.GsonBuilder;
 import com.google.gson.annotations.SerializedName;
diff --git a/src/test/java/com/android/tools/r8/gson/GsonNoDefaultConstructorTest.java b/src/test/java/com/android/tools/r8/gson/GsonNoDefaultConstructorTest.java
index cff8fc9..8cc370b 100644
--- a/src/test/java/com/android/tools/r8/gson/GsonNoDefaultConstructorTest.java
+++ b/src/test/java/com/android/tools/r8/gson/GsonNoDefaultConstructorTest.java
@@ -11,11 +11,11 @@
 import com.android.tools.r8.ProguardVersion;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.ToolHelper.DexVm.Version;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FoundMethodSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.gson.Gson;
 import com.google.gson.GsonBuilder;
 import com.google.gson.annotations.SerializedName;
diff --git a/src/test/java/com/android/tools/r8/gson/GsonTypeTokenTest.java b/src/test/java/com/android/tools/r8/gson/GsonTypeTokenTest.java
index d307d58..482b9e6 100644
--- a/src/test/java/com/android/tools/r8/gson/GsonTypeTokenTest.java
+++ b/src/test/java/com/android/tools/r8/gson/GsonTypeTokenTest.java
@@ -6,7 +6,7 @@
 import com.android.tools.r8.ProguardVersion;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.gson.GsonBuilder;
 import com.google.gson.reflect.TypeToken;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/horizontalclassmerging/ConditionalMethodRulesAndHorizontalMergingTest.java b/src/test/java/com/android/tools/r8/horizontalclassmerging/ConditionalMethodRulesAndHorizontalMergingTest.java
index 30f7171..38aea2d 100644
--- a/src/test/java/com/android/tools/r8/horizontalclassmerging/ConditionalMethodRulesAndHorizontalMergingTest.java
+++ b/src/test/java/com/android/tools/r8/horizontalclassmerging/ConditionalMethodRulesAndHorizontalMergingTest.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.horizontalclassmerging.ConditionalMethodRulesAndHorizontalMergingTest.Example2.MyFieldValuePrinter;
 import com.android.tools.r8.horizontalclassmerging.ConditionalMethodRulesAndHorizontalMergingTest.Example2.PrintableFieldInterface;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.lang.reflect.Field;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/inspection/FieldFlagsAndValueInspectionTest.java b/src/test/java/com/android/tools/r8/inspection/FieldFlagsAndValueInspectionTest.java
index 38e7f99..b7ccd9b 100644
--- a/src/test/java/com/android/tools/r8/inspection/FieldFlagsAndValueInspectionTest.java
+++ b/src/test/java/com/android/tools/r8/inspection/FieldFlagsAndValueInspectionTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.inspector.Inspector;
 import com.android.tools.r8.inspector.ValueInspector;
 import com.android.tools.r8.references.Reference;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Optional;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/inspection/FieldValueTypesInspectionTest.java b/src/test/java/com/android/tools/r8/inspection/FieldValueTypesInspectionTest.java
index cd867fc..c076bab 100644
--- a/src/test/java/com/android/tools/r8/inspection/FieldValueTypesInspectionTest.java
+++ b/src/test/java/com/android/tools/r8/inspection/FieldValueTypesInspectionTest.java
@@ -15,7 +15,7 @@
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.utils.internal.IntUtils;
 import com.android.tools.r8.utils.internal.LongUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/inspection/InspectionApiTest.java b/src/test/java/com/android/tools/r8/inspection/InspectionApiTest.java
index 6359c80..7d782b3 100644
--- a/src/test/java/com/android/tools/r8/inspection/InspectionApiTest.java
+++ b/src/test/java/com/android/tools/r8/inspection/InspectionApiTest.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.references.FieldReference;
 import com.android.tools.r8.references.MethodReference;
 import com.android.tools.r8.references.Reference;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Collections;
 import java.util.HashSet;
 import java.util.Set;
diff --git a/src/test/java/com/android/tools/r8/internal/ChromeCompilationBase.java b/src/test/java/com/android/tools/r8/internal/ChromeCompilationBase.java
index 60dcfdd..09370bb 100644
--- a/src/test/java/com/android/tools/r8/internal/ChromeCompilationBase.java
+++ b/src/test/java/com/android/tools/r8/internal/ChromeCompilationBase.java
@@ -8,7 +8,7 @@
 import static org.hamcrest.MatcherAssert.assertThat;
 
 import com.android.tools.r8.ToolHelper;
-import com.android.tools.r8.utils.FileUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/internal/LibrarySanitizer.java b/src/test/java/com/android/tools/r8/internal/LibrarySanitizer.java
index c28a84d..a825e28 100644
--- a/src/test/java/com/android/tools/r8/internal/LibrarySanitizer.java
+++ b/src/test/java/com/android/tools/r8/internal/LibrarySanitizer.java
@@ -9,7 +9,7 @@
 
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.ToolHelper.ProcessResult;
-import com.android.tools.r8.utils.FileUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/internal/Regression127524985.java b/src/test/java/com/android/tools/r8/internal/Regression127524985.java
index c9e61ed..523becf 100644
--- a/src/test/java/com/android/tools/r8/internal/Regression127524985.java
+++ b/src/test/java/com/android/tools/r8/internal/Regression127524985.java
@@ -13,8 +13,8 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ToolHelper;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.UnverifiableCfCodeDiagnostic;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.nio.file.Paths;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/internal/YouTubeCompilationTestBase.java b/src/test/java/com/android/tools/r8/internal/YouTubeCompilationTestBase.java
index df1101d..382c6ae 100644
--- a/src/test/java/com/android/tools/r8/internal/YouTubeCompilationTestBase.java
+++ b/src/test/java/com/android/tools/r8/internal/YouTubeCompilationTestBase.java
@@ -12,10 +12,10 @@
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.graph.DexItemFactory;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.ZipUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.analysis.ProtoApplicationStats;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.io.ByteStreams;
 import java.io.IOException;
diff --git a/src/test/java/com/android/tools/r8/internal/proto/ProtoBuilderShrinkingTest.java b/src/test/java/com/android/tools/r8/internal/proto/ProtoBuilderShrinkingTest.java
index daa097a..70d0df5 100644
--- a/src/test/java/com/android/tools/r8/internal/proto/ProtoBuilderShrinkingTest.java
+++ b/src/test/java/com/android/tools/r8/internal/proto/ProtoBuilderShrinkingTest.java
@@ -14,11 +14,11 @@
 import com.android.tools.r8.SingleTestRunResult;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.graph.DexType;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import com.google.common.collect.ImmutableList;
 import com.google.protobuf.InvalidProtocolBufferException;
diff --git a/src/test/java/com/android/tools/r8/internal/proto/ProtoShrinkingTestBase.java b/src/test/java/com/android/tools/r8/internal/proto/ProtoShrinkingTestBase.java
index 2b46a8a..fbe1add 100644
--- a/src/test/java/com/android/tools/r8/internal/proto/ProtoShrinkingTestBase.java
+++ b/src/test/java/com/android/tools/r8/internal/proto/ProtoShrinkingTestBase.java
@@ -20,10 +20,10 @@
 import com.android.tools.r8.ir.analysis.proto.RawMessageInfoDecoder;
 import com.android.tools.r8.ir.code.IRCode;
 import com.android.tools.r8.ir.code.InvokeMethod;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FoundClassSubject;
 import com.android.tools.r8.utils.codeinspector.FoundMethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import it.unimi.dsi.fastutil.ints.IntArrayList;
 import it.unimi.dsi.fastutil.ints.IntList;
 import java.util.HashMap;
diff --git a/src/test/java/com/android/tools/r8/internal/retrace/stacktraces/RetraceInternalStackTraceForTest.java b/src/test/java/com/android/tools/r8/internal/retrace/stacktraces/RetraceInternalStackTraceForTest.java
index 978e33a..b8e6700 100644
--- a/src/test/java/com/android/tools/r8/internal/retrace/stacktraces/RetraceInternalStackTraceForTest.java
+++ b/src/test/java/com/android/tools/r8/internal/retrace/stacktraces/RetraceInternalStackTraceForTest.java
@@ -6,7 +6,7 @@
 
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.retrace.stacktraces.StackTraceForTest;
-import com.android.tools.r8.utils.FileUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/ir/AssociativeIntTest.java b/src/test/java/com/android/tools/r8/ir/AssociativeIntTest.java
index 0047ded..a37bca5 100644
--- a/src/test/java/com/android/tools/r8/ir/AssociativeIntTest.java
+++ b/src/test/java/com/android/tools/r8/ir/AssociativeIntTest.java
@@ -12,11 +12,11 @@
 import com.android.tools.r8.R8FullTestBuilder;
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FoundMethodSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/ir/AssociativeLongTest.java b/src/test/java/com/android/tools/r8/ir/AssociativeLongTest.java
index 1d041b8..c42e6ce 100644
--- a/src/test/java/com/android/tools/r8/ir/AssociativeLongTest.java
+++ b/src/test/java/com/android/tools/r8/ir/AssociativeLongTest.java
@@ -10,10 +10,10 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FoundMethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/CheckIndexTest.java b/src/test/java/com/android/tools/r8/ir/CheckIndexTest.java
index eb170e5..17e8995 100644
--- a/src/test/java/com/android/tools/r8/ir/CheckIndexTest.java
+++ b/src/test/java/com/android/tools/r8/ir/CheckIndexTest.java
@@ -8,8 +8,8 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Assert;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/ir/ComposeBinopTest.java b/src/test/java/com/android/tools/r8/ir/ComposeBinopTest.java
index cd41b8d..45a4786 100644
--- a/src/test/java/com/android/tools/r8/ir/ComposeBinopTest.java
+++ b/src/test/java/com/android/tools/r8/ir/ComposeBinopTest.java
@@ -11,10 +11,10 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/IdentityAbsorbingBoolTest.java b/src/test/java/com/android/tools/r8/ir/IdentityAbsorbingBoolTest.java
index cda7825..c824b16 100644
--- a/src/test/java/com/android/tools/r8/ir/IdentityAbsorbingBoolTest.java
+++ b/src/test/java/com/android/tools/r8/ir/IdentityAbsorbingBoolTest.java
@@ -10,8 +10,8 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/IdentityAbsorbingIntTest.java b/src/test/java/com/android/tools/r8/ir/IdentityAbsorbingIntTest.java
index 9d7b58d..56b18c4 100644
--- a/src/test/java/com/android/tools/r8/ir/IdentityAbsorbingIntTest.java
+++ b/src/test/java/com/android/tools/r8/ir/IdentityAbsorbingIntTest.java
@@ -10,8 +10,8 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/IdentityAbsorbingLongTest.java b/src/test/java/com/android/tools/r8/ir/IdentityAbsorbingLongTest.java
index a1f0c1c..ae43306 100644
--- a/src/test/java/com/android/tools/r8/ir/IdentityAbsorbingLongTest.java
+++ b/src/test/java/com/android/tools/r8/ir/IdentityAbsorbingLongTest.java
@@ -10,8 +10,8 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/ShiftIssueTest.java b/src/test/java/com/android/tools/r8/ir/ShiftIssueTest.java
index e535d3e..1c84c0e 100644
--- a/src/test/java/com/android/tools/r8/ir/ShiftIssueTest.java
+++ b/src/test/java/com/android/tools/r8/ir/ShiftIssueTest.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/ShiftOppositeSignTest.java b/src/test/java/com/android/tools/r8/ir/ShiftOppositeSignTest.java
index e54e7b5..005ad55 100644
--- a/src/test/java/com/android/tools/r8/ir/ShiftOppositeSignTest.java
+++ b/src/test/java/com/android/tools/r8/ir/ShiftOppositeSignTest.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/SplitIntSwitchTest.java b/src/test/java/com/android/tools/r8/ir/SplitIntSwitchTest.java
index 78bf01e..e07e50d 100644
--- a/src/test/java/com/android/tools/r8/ir/SplitIntSwitchTest.java
+++ b/src/test/java/com/android/tools/r8/ir/SplitIntSwitchTest.java
@@ -8,8 +8,8 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Assert;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/ir/analysis/constant/B132897042.java b/src/test/java/com/android/tools/r8/ir/analysis/constant/B132897042.java
index 3415ebc..5362d2d 100644
--- a/src/test/java/com/android/tools/r8/ir/analysis/constant/B132897042.java
+++ b/src/test/java/com/android/tools/r8/ir/analysis/constant/B132897042.java
@@ -6,7 +6,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/analysis/initializedclasses/InitializedClassesOnNormalExitAnalysisTest.java b/src/test/java/com/android/tools/r8/ir/analysis/initializedclasses/InitializedClassesOnNormalExitAnalysisTest.java
index ea4ba2f..55fe955 100644
--- a/src/test/java/com/android/tools/r8/ir/analysis/initializedclasses/InitializedClassesOnNormalExitAnalysisTest.java
+++ b/src/test/java/com/android/tools/r8/ir/analysis/initializedclasses/InitializedClassesOnNormalExitAnalysisTest.java
@@ -13,11 +13,11 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/analysis/sideeffect/AnonymousObjectWithFinalizeTest.java b/src/test/java/com/android/tools/r8/ir/analysis/sideeffect/AnonymousObjectWithFinalizeTest.java
index cdb232d..dc01090 100644
--- a/src/test/java/com/android/tools/r8/ir/analysis/sideeffect/AnonymousObjectWithFinalizeTest.java
+++ b/src/test/java/com/android/tools/r8/ir/analysis/sideeffect/AnonymousObjectWithFinalizeTest.java
@@ -6,7 +6,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.TimeUnit;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/ir/analysis/type/ConstrainedPrimitiveTypeTest.java b/src/test/java/com/android/tools/r8/ir/analysis/type/ConstrainedPrimitiveTypeTest.java
index 693fb24..dd0d2f8 100644
--- a/src/test/java/com/android/tools/r8/ir/analysis/type/ConstrainedPrimitiveTypeTest.java
+++ b/src/test/java/com/android/tools/r8/ir/analysis/type/ConstrainedPrimitiveTypeTest.java
@@ -17,7 +17,7 @@
 import com.android.tools.r8.ir.code.ConstNumber;
 import com.android.tools.r8.ir.code.IRCode;
 import com.android.tools.r8.ir.code.Instruction;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.Streams;
 import java.util.function.Consumer;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/ir/analysis/type/MissingClassesJoinTest.java b/src/test/java/com/android/tools/r8/ir/analysis/type/MissingClassesJoinTest.java
index 2f6274c..0818265 100644
--- a/src/test/java/com/android/tools/r8/ir/analysis/type/MissingClassesJoinTest.java
+++ b/src/test/java/com/android/tools/r8/ir/analysis/type/MissingClassesJoinTest.java
@@ -21,9 +21,9 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.references.MethodReference;
 import com.android.tools.r8.utils.MethodReferenceUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.UnverifiableCfCodeDiagnostic;
 import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.base.Throwables;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/ir/analysis/type/TypeConstraintOnTrivialPhiTest.java b/src/test/java/com/android/tools/r8/ir/analysis/type/TypeConstraintOnTrivialPhiTest.java
index 6fa16de..2e05335 100644
--- a/src/test/java/com/android/tools/r8/ir/analysis/type/TypeConstraintOnTrivialPhiTest.java
+++ b/src/test/java/com/android/tools/r8/ir/analysis/type/TypeConstraintOnTrivialPhiTest.java
@@ -16,7 +16,7 @@
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.smali.SmaliBuilder;
 import com.android.tools.r8.utils.AndroidApp;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import com.google.common.collect.ImmutableList;
 import java.util.function.Consumer;
diff --git a/src/test/java/com/android/tools/r8/ir/analysis/type/UnconstrainedPrimitiveTypeTest.java b/src/test/java/com/android/tools/r8/ir/analysis/type/UnconstrainedPrimitiveTypeTest.java
index d0b9c70..7892372 100644
--- a/src/test/java/com/android/tools/r8/ir/analysis/type/UnconstrainedPrimitiveTypeTest.java
+++ b/src/test/java/com/android/tools/r8/ir/analysis/type/UnconstrainedPrimitiveTypeTest.java
@@ -16,7 +16,7 @@
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.smali.SmaliBuilder;
 import com.android.tools.r8.utils.AndroidApp;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.function.Consumer;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/ir/desugar/backports/GenerateBackportMethods.java b/src/test/java/com/android/tools/r8/ir/desugar/backports/GenerateBackportMethods.java
index 54532a8..163f51c 100644
--- a/src/test/java/com/android/tools/r8/ir/desugar/backports/GenerateBackportMethods.java
+++ b/src/test/java/com/android/tools/r8/ir/desugar/backports/GenerateBackportMethods.java
@@ -21,7 +21,7 @@
 import com.android.tools.r8.ir.desugar.backports.BackportMethodsStub.MathStub;
 import com.android.tools.r8.ir.desugar.backports.BackportMethodsStub.UnsafeStub;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.FileUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import java.io.IOException;
diff --git a/src/test/java/com/android/tools/r8/ir/desugar/varhandle/GenerateVarHandleMethods.java b/src/test/java/com/android/tools/r8/ir/desugar/varhandle/GenerateVarHandleMethods.java
index cb706c4..ea44bd6 100644
--- a/src/test/java/com/android/tools/r8/ir/desugar/varhandle/GenerateVarHandleMethods.java
+++ b/src/test/java/com/android/tools/r8/ir/desugar/varhandle/GenerateVarHandleMethods.java
@@ -17,7 +17,7 @@
 import com.android.tools.r8.graph.DexProto;
 import com.android.tools.r8.graph.DexType;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.FileUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.ImmutableSet;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/AlwaysThrowNullTest.java b/src/test/java/com/android/tools/r8/ir/optimize/AlwaysThrowNullTest.java
index fcf8304..0e99853 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/AlwaysThrowNullTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/AlwaysThrowNullTest.java
@@ -18,11 +18,11 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Streams;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/B370217724Test.java b/src/test/java/com/android/tools/r8/ir/optimize/B370217724Test.java
index 2e862cb..43fe563 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/B370217724Test.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/B370217724Test.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/DivisionToShiftIntTest.java b/src/test/java/com/android/tools/r8/ir/optimize/DivisionToShiftIntTest.java
index adad3bf..cd6905c 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/DivisionToShiftIntTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/DivisionToShiftIntTest.java
@@ -14,10 +14,10 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.references.MethodReference;
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeMatchers;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.lang.reflect.Method;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/DivisionToShiftLongTest.java b/src/test/java/com/android/tools/r8/ir/optimize/DivisionToShiftLongTest.java
index 52a25d0..1a88e40 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/DivisionToShiftLongTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/DivisionToShiftLongTest.java
@@ -13,10 +13,10 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.references.MethodReference;
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeMatchers;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.lang.reflect.Method;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/MemberValuePropagationTest.java b/src/test/java/com/android/tools/r8/ir/optimize/MemberValuePropagationTest.java
index 7d1141c..d4c00f5 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/MemberValuePropagationTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/MemberValuePropagationTest.java
@@ -8,10 +8,10 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.ToolHelper;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
+import com.android.tools.r8.utils.internal.FileUtils;
 import java.nio.file.Path;
 import java.nio.file.Paths;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/ObjectsRequireNonNullTest.java b/src/test/java/com/android/tools/r8/ir/optimize/ObjectsRequireNonNullTest.java
index 7f82bcf..d4bfedf 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/ObjectsRequireNonNullTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/ObjectsRequireNonNullTest.java
@@ -19,11 +19,11 @@
 import com.android.tools.r8.ToolHelper.DexVm.Version;
 import com.android.tools.r8.graph.DexMethod;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.Streams;
 import java.util.Objects;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/R8InliningRegressionTests.java b/src/test/java/com/android/tools/r8/ir/optimize/R8InliningRegressionTests.java
index 8f1c4af..13471dc 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/R8InliningRegressionTests.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/R8InliningRegressionTests.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.utils.AndroidApp;
-import com.android.tools.r8.utils.FileUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import java.nio.file.Path;
 import java.nio.file.Paths;
 import java.util.Collections;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/R8InliningTest.java b/src/test/java/com/android/tools/r8/ir/optimize/R8InliningTest.java
index 88472d8..af86791 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/R8InliningTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/R8InliningTest.java
@@ -22,16 +22,16 @@
 import com.android.tools.r8.graph.DexType;
 import com.android.tools.r8.horizontalclassmerging.HorizontallyMergedClasses;
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
-import com.android.tools.r8.utils.internal.BooleanUtils;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.internal.IntBox;
 import com.android.tools.r8.utils.ZipUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.InvokeInstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.IntBox;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.nio.file.Files;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/RedundantConstNumberRemovalTest.java b/src/test/java/com/android/tools/r8/ir/optimize/RedundantConstNumberRemovalTest.java
index d50fb21..69a8c42 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/RedundantConstNumberRemovalTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/RedundantConstNumberRemovalTest.java
@@ -20,10 +20,10 @@
 import com.android.tools.r8.ir.code.IRCode;
 import com.android.tools.r8.ir.code.Instruction;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.Streams;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/boxedprimitives/ReverseBoxingOperationsTest.java b/src/test/java/com/android/tools/r8/ir/optimize/boxedprimitives/ReverseBoxingOperationsTest.java
index c3968fe..430fede 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/boxedprimitives/ReverseBoxingOperationsTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/boxedprimitives/ReverseBoxingOperationsTest.java
@@ -14,8 +14,8 @@
 import com.android.tools.r8.graph.DexItemFactory;
 import com.android.tools.r8.graph.DexMethod;
 import com.android.tools.r8.graph.DexType;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.Sets;
 import java.util.ArrayList;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/boxedprimitives/UnboxToCheckNotNullTest.java b/src/test/java/com/android/tools/r8/ir/optimize/boxedprimitives/UnboxToCheckNotNullTest.java
index 2001277..aeb608c 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/boxedprimitives/UnboxToCheckNotNullTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/boxedprimitives/UnboxToCheckNotNullTest.java
@@ -14,8 +14,8 @@
 import com.android.tools.r8.graph.DexMethod;
 import com.android.tools.r8.graph.DexType;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.Sets;
 import java.util.ArrayList;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/callsites/CallSiteOptimizationWithInvokeCustomTargetTest.java b/src/test/java/com/android/tools/r8/ir/optimize/callsites/CallSiteOptimizationWithInvokeCustomTargetTest.java
index 0672de1..973f02b 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/callsites/CallSiteOptimizationWithInvokeCustomTargetTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/callsites/CallSiteOptimizationWithInvokeCustomTargetTest.java
@@ -13,8 +13,8 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.lang.invoke.CallSite;
 import java.lang.invoke.ConstantCallSite;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/canonicalization/ConstClassCanonicalizationTest.java b/src/test/java/com/android/tools/r8/ir/optimize/canonicalization/ConstClassCanonicalizationTest.java
index f4bd2f4..860d60d 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/canonicalization/ConstClassCanonicalizationTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/canonicalization/ConstClassCanonicalizationTest.java
@@ -15,13 +15,13 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.ir.optimize.canonicalization.ConstClassMain.Outer;
 import com.android.tools.r8.ir.optimize.canonicalization.ConstClassMain.Outer.Inner;
-import com.android.tools.r8.utils.internal.BooleanUtils;
 import com.android.tools.r8.utils.InternalOptions;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/canonicalization/DexItemBasedConstStringCanonicalizationTest.java b/src/test/java/com/android/tools/r8/ir/optimize/canonicalization/DexItemBasedConstStringCanonicalizationTest.java
index 372423d..053c35c 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/canonicalization/DexItemBasedConstStringCanonicalizationTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/canonicalization/DexItemBasedConstStringCanonicalizationTest.java
@@ -13,11 +13,11 @@
 import com.android.tools.r8.SingleTestRunResult;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.ir.optimize.reflection.GetNameTestBase;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject.JumboStringMode;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.Streams;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/canonicalization/IdempotentFunctionCallCanonicalizationTest.java b/src/test/java/com/android/tools/r8/ir/optimize/canonicalization/IdempotentFunctionCallCanonicalizationTest.java
index 254e603..04d8c3d 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/canonicalization/IdempotentFunctionCallCanonicalizationTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/canonicalization/IdempotentFunctionCallCanonicalizationTest.java
@@ -16,10 +16,10 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.graph.DexMethod;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.Streams;
 import java.util.ArrayList;
 import java.util.HashMap;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/canonicalization/IllegalAccessConstClassTest.java b/src/test/java/com/android/tools/r8/ir/optimize/canonicalization/IllegalAccessConstClassTest.java
index c186bfb..6559676 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/canonicalization/IllegalAccessConstClassTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/canonicalization/IllegalAccessConstClassTest.java
@@ -11,11 +11,11 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.utils.InternalOptions;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/canonicalization/StringCanonicalizationTest.java b/src/test/java/com/android/tools/r8/ir/optimize/canonicalization/StringCanonicalizationTest.java
index 175e903..db2eb23 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/canonicalization/StringCanonicalizationTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/canonicalization/StringCanonicalizationTest.java
@@ -14,11 +14,11 @@
 import com.android.tools.r8.TestCompileResult;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject.JumboStringMode;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.Streams;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/canonicalization/StringInMonitorTest.java b/src/test/java/com/android/tools/r8/ir/optimize/canonicalization/StringInMonitorTest.java
index 4517502..6e78c77 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/canonicalization/StringInMonitorTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/canonicalization/StringInMonitorTest.java
@@ -17,7 +17,6 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionOffsetSubject;
@@ -26,6 +25,7 @@
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
 import com.android.tools.r8.utils.codeinspector.RangeSubject;
 import com.android.tools.r8.utils.codeinspector.TryCatchSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.Streams;
 import java.util.Iterator;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/canonicalization/UnresolvableLibraryConstClassTest.java b/src/test/java/com/android/tools/r8/ir/optimize/canonicalization/UnresolvableLibraryConstClassTest.java
index 7e7f5b4..264d300 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/canonicalization/UnresolvableLibraryConstClassTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/canonicalization/UnresolvableLibraryConstClassTest.java
@@ -13,11 +13,11 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.utils.InternalOptions;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/checkcast/ArrayInterfaceArrayCheckCastTest.java b/src/test/java/com/android/tools/r8/ir/optimize/checkcast/ArrayInterfaceArrayCheckCastTest.java
index 00e8742..ca9e6d7 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/checkcast/ArrayInterfaceArrayCheckCastTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/checkcast/ArrayInterfaceArrayCheckCastTest.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/checkcast/CastInDeadCodeafterInstanceOfOptimizationTest.java b/src/test/java/com/android/tools/r8/ir/optimize/checkcast/CastInDeadCodeafterInstanceOfOptimizationTest.java
index c690efd..115b1b7 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/checkcast/CastInDeadCodeafterInstanceOfOptimizationTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/checkcast/CastInDeadCodeafterInstanceOfOptimizationTest.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/checkcast/CheckCastInterfaceArrayTest.java b/src/test/java/com/android/tools/r8/ir/optimize/checkcast/CheckCastInterfaceArrayTest.java
index 6d45501..523558f 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/checkcast/CheckCastInterfaceArrayTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/checkcast/CheckCastInterfaceArrayTest.java
@@ -6,7 +6,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Assume;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/checkcast/CheckCastNullForTypeTest.java b/src/test/java/com/android/tools/r8/ir/optimize/checkcast/CheckCastNullForTypeTest.java
index c0a57f7..981e2c5 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/checkcast/CheckCastNullForTypeTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/checkcast/CheckCastNullForTypeTest.java
@@ -11,9 +11,9 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/checkcast/InterfaceArrayCheckCastTest.java b/src/test/java/com/android/tools/r8/ir/optimize/checkcast/InterfaceArrayCheckCastTest.java
index 939890a..19212e2 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/checkcast/InterfaceArrayCheckCastTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/checkcast/InterfaceArrayCheckCastTest.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/checkcast/TrivialArrayCheckCastTest.java b/src/test/java/com/android/tools/r8/ir/optimize/checkcast/TrivialArrayCheckCastTest.java
index 25ba251..9e8f0d4 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/checkcast/TrivialArrayCheckCastTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/checkcast/TrivialArrayCheckCastTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.InternalOptions;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/classinitializerdefaults/NonFinalFieldWithDefaultValueTest.java b/src/test/java/com/android/tools/r8/ir/optimize/classinitializerdefaults/NonFinalFieldWithDefaultValueTest.java
index ead61d9..08e2f97 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/classinitializerdefaults/NonFinalFieldWithDefaultValueTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/classinitializerdefaults/NonFinalFieldWithDefaultValueTest.java
@@ -14,10 +14,10 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FieldSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/classinliner/ClassInlinerBuilderWithControlFlowTest.java b/src/test/java/com/android/tools/r8/ir/optimize/classinliner/ClassInlinerBuilderWithControlFlowTest.java
index 93dba41..d999f16 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/classinliner/ClassInlinerBuilderWithControlFlowTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/classinliner/ClassInlinerBuilderWithControlFlowTest.java
@@ -11,9 +11,9 @@
 
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Collections;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/classinliner/ClassInlinerBuilderWithMoreControlFlowTest.java b/src/test/java/com/android/tools/r8/ir/optimize/classinliner/ClassInlinerBuilderWithMoreControlFlowTest.java
index 61c7fcb..8bbd00f 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/classinliner/ClassInlinerBuilderWithMoreControlFlowTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/classinliner/ClassInlinerBuilderWithMoreControlFlowTest.java
@@ -11,9 +11,9 @@
 
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Collections;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/classinliner/ClassInlinerSimplePairBuilderTest.java b/src/test/java/com/android/tools/r8/ir/optimize/classinliner/ClassInlinerSimplePairBuilderTest.java
index a78e0d3..d5e089d 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/classinliner/ClassInlinerSimplePairBuilderTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/classinliner/ClassInlinerSimplePairBuilderTest.java
@@ -15,9 +15,9 @@
 import com.android.tools.r8.NoHorizontalClassMerging;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableSet;
 import java.util.Set;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/classinliner/ClassInlinerSimplePairBuilderWithMultipleBuildsTest.java b/src/test/java/com/android/tools/r8/ir/optimize/classinliner/ClassInlinerSimplePairBuilderWithMultipleBuildsTest.java
index 6218ee7..84b047c 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/classinliner/ClassInlinerSimplePairBuilderWithMultipleBuildsTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/classinliner/ClassInlinerSimplePairBuilderWithMultipleBuildsTest.java
@@ -12,9 +12,9 @@
 import com.android.tools.r8.AlwaysInline;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Collections;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/classinliner/ClassInlinerTest.java b/src/test/java/com/android/tools/r8/ir/optimize/classinliner/ClassInlinerTest.java
index c151531..968d4de 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/classinliner/ClassInlinerTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/classinliner/ClassInlinerTest.java
@@ -35,11 +35,11 @@
 import com.android.tools.r8.jasmin.JasminBuilder;
 import com.android.tools.r8.jasmin.JasminBuilder.ClassBuilder;
 import com.android.tools.r8.utils.AndroidApp;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FoundClassSubject;
 import com.android.tools.r8.utils.codeinspector.HorizontallyMergedClassesInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.Sets;
 import java.util.Collections;
 import java.util.HashSet;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/classinliner/ClassInlinerTupleBuilderConstructorsTest.java b/src/test/java/com/android/tools/r8/ir/optimize/classinliner/ClassInlinerTupleBuilderConstructorsTest.java
index 29618d5..ed5c2ee 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/classinliner/ClassInlinerTupleBuilderConstructorsTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/classinliner/ClassInlinerTupleBuilderConstructorsTest.java
@@ -12,9 +12,9 @@
 import com.android.tools.r8.AlwaysClassInline;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Collections;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/classinliner/nonpublicsubtype/ClassInlineNonPublicSubtypeTest.java b/src/test/java/com/android/tools/r8/ir/optimize/classinliner/nonpublicsubtype/ClassInlineNonPublicSubtypeTest.java
index ce7a04f..adc2083 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/classinliner/nonpublicsubtype/ClassInlineNonPublicSubtypeTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/classinliner/nonpublicsubtype/ClassInlineNonPublicSubtypeTest.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ir.optimize.classinliner.nonpublicsubtype.subpkg.Utils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/dynamictype/DynamicTypeOptimizationTest.java b/src/test/java/com/android/tools/r8/ir/optimize/dynamictype/DynamicTypeOptimizationTest.java
index a93bbe0..295de3a 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/dynamictype/DynamicTypeOptimizationTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/dynamictype/DynamicTypeOptimizationTest.java
@@ -15,10 +15,10 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/effectivelytrivialphioptimization/Regress345248270ConstClassTest.java b/src/test/java/com/android/tools/r8/ir/optimize/effectivelytrivialphioptimization/Regress345248270ConstClassTest.java
index 684f3a4..0e95f18 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/effectivelytrivialphioptimization/Regress345248270ConstClassTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/effectivelytrivialphioptimization/Regress345248270ConstClassTest.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ir.optimize.effectivelytrivialphioptimization.b345248270.I;
 import com.android.tools.r8.ir.optimize.effectivelytrivialphioptimization.b345248270.PublicAccessor;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/effectivelytrivialphioptimization/Regress345248270Test.java b/src/test/java/com/android/tools/r8/ir/optimize/effectivelytrivialphioptimization/Regress345248270Test.java
index 0b0fcb3..30958da 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/effectivelytrivialphioptimization/Regress345248270Test.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/effectivelytrivialphioptimization/Regress345248270Test.java
@@ -12,10 +12,10 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ir.optimize.effectivelytrivialphioptimization.b345248270.I;
 import com.android.tools.r8.ir.optimize.effectivelytrivialphioptimization.b345248270.PublicAccessor;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.Matchers;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/fields/FieldAnalysisTest.java b/src/test/java/com/android/tools/r8/ir/optimize/fields/FieldAnalysisTest.java
index 4b65766..579208a 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/fields/FieldAnalysisTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/fields/FieldAnalysisTest.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/ifs/IfThrowNullPointerExceptionTest.java b/src/test/java/com/android/tools/r8/ir/optimize/ifs/IfThrowNullPointerExceptionTest.java
index 4c00091..45147c5 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/ifs/IfThrowNullPointerExceptionTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/ifs/IfThrowNullPointerExceptionTest.java
@@ -17,11 +17,11 @@
 import com.android.tools.r8.ir.code.BasicBlock;
 import com.android.tools.r8.ir.code.IRCode;
 import com.android.tools.r8.ir.code.Instruction;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/ifs/Regress343136777Test.java b/src/test/java/com/android/tools/r8/ir/optimize/ifs/Regress343136777Test.java
index 1b8c4ce..913ffc5 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/ifs/Regress343136777Test.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/ifs/Regress343136777Test.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/inliner/BridgeWithCastsInliningTest.java b/src/test/java/com/android/tools/r8/ir/optimize/inliner/BridgeWithCastsInliningTest.java
index 69d3862..073bc97 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/inliner/BridgeWithCastsInliningTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/inliner/BridgeWithCastsInliningTest.java
@@ -13,12 +13,12 @@
 import com.android.tools.r8.NeverSingleCallerInline;
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.internal.BooleanUtils;
 import com.android.tools.r8.utils.InternalOptions.InlinerOptions;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/inliner/BridgeWithUnboxingInliningTest.java b/src/test/java/com/android/tools/r8/ir/optimize/inliner/BridgeWithUnboxingInliningTest.java
index 989df46..20355ab 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/inliner/BridgeWithUnboxingInliningTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/inliner/BridgeWithUnboxingInliningTest.java
@@ -13,12 +13,12 @@
 import com.android.tools.r8.NeverSingleCallerInline;
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.internal.BooleanUtils;
 import com.android.tools.r8.utils.InternalOptions.InlinerOptions;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/inliner/DoubleInliningInvokeSuperTest.java b/src/test/java/com/android/tools/r8/ir/optimize/inliner/DoubleInliningInvokeSuperTest.java
index 46fb258..43820ad 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/inliner/DoubleInliningInvokeSuperTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/inliner/DoubleInliningInvokeSuperTest.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/inliner/InlineCatchHandlerWithLibraryTypeTest.java b/src/test/java/com/android/tools/r8/ir/optimize/inliner/InlineCatchHandlerWithLibraryTypeTest.java
index 4ff3f4f..423cec6 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/inliner/InlineCatchHandlerWithLibraryTypeTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/inliner/InlineCatchHandlerWithLibraryTypeTest.java
@@ -15,9 +15,9 @@
 import com.android.tools.r8.ToolHelper.DexVm.Version;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.Streams;
 import java.io.IOException;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/inliner/InlineInvokeWithNullableReceiverTest.java b/src/test/java/com/android/tools/r8/ir/optimize/inliner/InlineInvokeWithNullableReceiverTest.java
index e1aca00..fb5d0b4 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/inliner/InlineInvokeWithNullableReceiverTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/inliner/InlineInvokeWithNullableReceiverTest.java
@@ -15,11 +15,11 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/inliner/InlineNonReboundFieldTest.java b/src/test/java/com/android/tools/r8/ir/optimize/inliner/InlineNonReboundFieldTest.java
index 0179d87..56e5ce6 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/inliner/InlineNonReboundFieldTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/inliner/InlineNonReboundFieldTest.java
@@ -13,9 +13,9 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ir.optimize.inliner.testclasses.Greeting;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/inliner/InlineSynchronizedMethodTest.java b/src/test/java/com/android/tools/r8/ir/optimize/inliner/InlineSynchronizedMethodTest.java
index 966355a..334831c 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/inliner/InlineSynchronizedMethodTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/inliner/InlineSynchronizedMethodTest.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/inliner/InlineWithSimpleFieldNoValue.java b/src/test/java/com/android/tools/r8/ir/optimize/inliner/InlineWithSimpleFieldNoValue.java
index eac5881..1586761 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/inliner/InlineWithSimpleFieldNoValue.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/inliner/InlineWithSimpleFieldNoValue.java
@@ -8,7 +8,7 @@
 
 import com.android.tools.r8.R8TestRunResult;
 import com.android.tools.r8.TestBase;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 
 class TestClass {
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/inliner/InliningAfterClassInitializationTest.java b/src/test/java/com/android/tools/r8/ir/optimize/inliner/InliningAfterClassInitializationTest.java
index 5905b26..aff9642 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/inliner/InliningAfterClassInitializationTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/inliner/InliningAfterClassInitializationTest.java
@@ -17,10 +17,10 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Objects;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/inliner/InliningFromCurrentClassTest.java b/src/test/java/com/android/tools/r8/ir/optimize/inliner/InliningFromCurrentClassTest.java
index eff0507..304c37b 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/inliner/InliningFromCurrentClassTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/inliner/InliningFromCurrentClassTest.java
@@ -14,10 +14,10 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/inliner/InliningIntoVisibilityBridgeTest.java b/src/test/java/com/android/tools/r8/ir/optimize/inliner/InliningIntoVisibilityBridgeTest.java
index abbc673..9427fa5 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/inliner/InliningIntoVisibilityBridgeTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/inliner/InliningIntoVisibilityBridgeTest.java
@@ -15,10 +15,10 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.ir.optimize.inliner.testclasses.InliningIntoVisibilityBridgeTestClasses;
 import com.android.tools.r8.ir.optimize.inliner.testclasses.InliningIntoVisibilityBridgeTestClasses.InliningIntoVisibilityBridgeTestClassB;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/inliner/InliningWithClassInitializerTest.java b/src/test/java/com/android/tools/r8/ir/optimize/inliner/InliningWithClassInitializerTest.java
index 3043e74..5111f95 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/inliner/InliningWithClassInitializerTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/inliner/InliningWithClassInitializerTest.java
@@ -14,10 +14,10 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/inliner/InterfaceInvokeWithObjectReceiverInliningTest.java b/src/test/java/com/android/tools/r8/ir/optimize/inliner/InterfaceInvokeWithObjectReceiverInliningTest.java
index af48a84..d47015d 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/inliner/InterfaceInvokeWithObjectReceiverInliningTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/inliner/InterfaceInvokeWithObjectReceiverInliningTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.transformers.ClassFileTransformer.MethodPredicate;
 import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/inliner/conditionalsimpleinlining/SimpleIfNullOrNotNullInliningTest.java b/src/test/java/com/android/tools/r8/ir/optimize/inliner/conditionalsimpleinlining/SimpleIfNullOrNotNullInliningTest.java
index 6dc07cc..a1b965f 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/inliner/conditionalsimpleinlining/SimpleIfNullOrNotNullInliningTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/inliner/conditionalsimpleinlining/SimpleIfNullOrNotNullInliningTest.java
@@ -14,11 +14,11 @@
 import com.android.tools.r8.NeverSingleCallerInline;
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/inliner/conditionalsimpleinlining/SimpleIfTrueOrFalseInliningTest.java b/src/test/java/com/android/tools/r8/ir/optimize/inliner/conditionalsimpleinlining/SimpleIfTrueOrFalseInliningTest.java
index 57309a9..f23356f 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/inliner/conditionalsimpleinlining/SimpleIfTrueOrFalseInliningTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/inliner/conditionalsimpleinlining/SimpleIfTrueOrFalseInliningTest.java
@@ -14,11 +14,11 @@
 import com.android.tools.r8.NeverSingleCallerInline;
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/inliner/conditionalsimpleinlining/SwitchWithSimpleCasesInliningKotlinTest.java b/src/test/java/com/android/tools/r8/ir/optimize/inliner/conditionalsimpleinlining/SwitchWithSimpleCasesInliningKotlinTest.java
index 15b2e3a..f4c5100 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/inliner/conditionalsimpleinlining/SwitchWithSimpleCasesInliningKotlinTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/inliner/conditionalsimpleinlining/SwitchWithSimpleCasesInliningKotlinTest.java
@@ -13,11 +13,11 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Paths;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/inliner/conditionalsimpleinlining/SwitchWithSimpleCasesInliningTest.java b/src/test/java/com/android/tools/r8/ir/optimize/inliner/conditionalsimpleinlining/SwitchWithSimpleCasesInliningTest.java
index 8365b22..a1906e8 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/inliner/conditionalsimpleinlining/SwitchWithSimpleCasesInliningTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/inliner/conditionalsimpleinlining/SwitchWithSimpleCasesInliningTest.java
@@ -13,10 +13,10 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.transformers.MethodTransformer;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/inliner/interfacemethods/InlineDefaultInterfaceMethodTest.java b/src/test/java/com/android/tools/r8/ir/optimize/inliner/interfacemethods/InlineDefaultInterfaceMethodTest.java
index 27816da..eea9011 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/inliner/interfacemethods/InlineDefaultInterfaceMethodTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/inliner/interfacemethods/InlineDefaultInterfaceMethodTest.java
@@ -11,8 +11,8 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/inliner/interfacemethods/InlineStaticInterfaceMethodTest.java b/src/test/java/com/android/tools/r8/ir/optimize/inliner/interfacemethods/InlineStaticInterfaceMethodTest.java
index 4e1bc46..dc1a064 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/inliner/interfacemethods/InlineStaticInterfaceMethodTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/inliner/interfacemethods/InlineStaticInterfaceMethodTest.java
@@ -9,8 +9,8 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/instanceofremoval/InstanceOfRemovalTest.java b/src/test/java/com/android/tools/r8/ir/optimize/instanceofremoval/InstanceOfRemovalTest.java
index a2f92ac..5eaea52 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/instanceofremoval/InstanceOfRemovalTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/instanceofremoval/InstanceOfRemovalTest.java
@@ -10,11 +10,11 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.Streams;
 import java.util.Iterator;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/instanceofremoval/ZipFileInstanceOfAutoCloseableTest.java b/src/test/java/com/android/tools/r8/ir/optimize/instanceofremoval/ZipFileInstanceOfAutoCloseableTest.java
index 455f5c0..a745fa4 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/instanceofremoval/ZipFileInstanceOfAutoCloseableTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/instanceofremoval/ZipFileInstanceOfAutoCloseableTest.java
@@ -22,8 +22,8 @@
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.AndroidApp;
 import com.android.tools.r8.utils.InternalOptions;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.ZipUtils.ZipBuilder;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.timing.Timing;
 import java.io.IOException;
 import java.nio.channels.Channel;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/library/ObjectEqualsTest.java b/src/test/java/com/android/tools/r8/ir/optimize/library/ObjectEqualsTest.java
index 11b83ff..040085d 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/library/ObjectEqualsTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/library/ObjectEqualsTest.java
@@ -12,11 +12,10 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.ir.optimize.library.ObjectsEqualsTest.Main;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeMatchers;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.hamcrest.Matcher;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/logging/AndroidLogRemovalTest.java b/src/test/java/com/android/tools/r8/ir/optimize/logging/AndroidLogRemovalTest.java
index af5c831..ceeca0f 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/logging/AndroidLogRemovalTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/logging/AndroidLogRemovalTest.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.errors.DuplicateTypeInProgramAndLibraryDiagnostic;
 import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import com.google.common.collect.ImmutableList;
 import java.lang.annotation.Retention;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/membervaluepropagation/DefaultFieldValueJoinerWithServiceLoaderTest.java b/src/test/java/com/android/tools/r8/ir/optimize/membervaluepropagation/DefaultFieldValueJoinerWithServiceLoaderTest.java
index 1efc4cb..e4595fa 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/membervaluepropagation/DefaultFieldValueJoinerWithServiceLoaderTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/membervaluepropagation/DefaultFieldValueJoinerWithServiceLoaderTest.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.origin.Origin;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.Lists;
 import java.util.List;
 import java.util.ServiceLoader;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/membervaluepropagation/InstanceFieldValuePropagationTest.java b/src/test/java/com/android/tools/r8/ir/optimize/membervaluepropagation/InstanceFieldValuePropagationTest.java
index 2982706..ad6e450 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/membervaluepropagation/InstanceFieldValuePropagationTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/membervaluepropagation/InstanceFieldValuePropagationTest.java
@@ -13,11 +13,11 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/membervaluepropagation/LibraryFieldPropagationTest.java b/src/test/java/com/android/tools/r8/ir/optimize/membervaluepropagation/LibraryFieldPropagationTest.java
index 6a9143c..9abb3dc 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/membervaluepropagation/LibraryFieldPropagationTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/membervaluepropagation/LibraryFieldPropagationTest.java
@@ -11,12 +11,12 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.jasmin.JasminBuilder;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.BeforeClass;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/membervaluepropagation/RedundantStaticPutWithClassInitializationTest.java b/src/test/java/com/android/tools/r8/ir/optimize/membervaluepropagation/RedundantStaticPutWithClassInitializationTest.java
index 9a8bae6..ddf2152 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/membervaluepropagation/RedundantStaticPutWithClassInitializationTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/membervaluepropagation/RedundantStaticPutWithClassInitializationTest.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/membervaluepropagation/SdkIntMemberValuePropagationTest.java b/src/test/java/com/android/tools/r8/ir/optimize/membervaluepropagation/SdkIntMemberValuePropagationTest.java
index 1d7cbd2..cf0d272 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/membervaluepropagation/SdkIntMemberValuePropagationTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/membervaluepropagation/SdkIntMemberValuePropagationTest.java
@@ -14,11 +14,11 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.graph.AccessFlags;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/membervaluepropagation/StaticFieldPropagationTest.java b/src/test/java/com/android/tools/r8/ir/optimize/membervaluepropagation/StaticFieldPropagationTest.java
index 9a7d252..e246c06 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/membervaluepropagation/StaticFieldPropagationTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/membervaluepropagation/StaticFieldPropagationTest.java
@@ -12,11 +12,11 @@
 import com.android.tools.r8.NeverInline;
 import com.android.tools.r8.R8TestRunResult;
 import com.android.tools.r8.TestBase;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 
 public class StaticFieldPropagationTest extends TestBase {
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/outliner/MultipleOutlinesInMethodWithExceptionHandlerTest.java b/src/test/java/com/android/tools/r8/ir/optimize/outliner/MultipleOutlinesInMethodWithExceptionHandlerTest.java
index 41fc7d0..bad21b5 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/outliner/MultipleOutlinesInMethodWithExceptionHandlerTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/outliner/MultipleOutlinesInMethodWithExceptionHandlerTest.java
@@ -19,12 +19,12 @@
 import com.android.tools.r8.dex.code.DexMulInt2Addr;
 import com.android.tools.r8.dex.code.DexReturn;
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.CodeMatchers;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/outliner/OutlineInvokeStaticBailoutTest.java b/src/test/java/com/android/tools/r8/ir/optimize/outliner/OutlineInvokeStaticBailoutTest.java
index a127403..a69884b 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/outliner/OutlineInvokeStaticBailoutTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/outliner/OutlineInvokeStaticBailoutTest.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/outliner/OutlineMappingInformationTest.java b/src/test/java/com/android/tools/r8/ir/optimize/outliner/OutlineMappingInformationTest.java
index d28445f..f750fdf 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/outliner/OutlineMappingInformationTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/outliner/OutlineMappingInformationTest.java
@@ -11,9 +11,9 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.naming.retrace.StackTrace;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.HorizontallyMergedClassesInspector;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Before;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/outliner/OutlinesWithNonNullTest.java b/src/test/java/com/android/tools/r8/ir/optimize/outliner/OutlinesWithNonNullTest.java
index b036380..f12a1fd 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/outliner/OutlinesWithNonNullTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/outliner/OutlinesWithNonNullTest.java
@@ -13,11 +13,11 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.CodeMatchers;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/outliner/arraytypes/OutlinesWithClassArrayTypeArguments.java b/src/test/java/com/android/tools/r8/ir/optimize/outliner/arraytypes/OutlinesWithClassArrayTypeArguments.java
index fd007b6..c848d5f 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/outliner/arraytypes/OutlinesWithClassArrayTypeArguments.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/outliner/arraytypes/OutlinesWithClassArrayTypeArguments.java
@@ -12,11 +12,11 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.CodeMatchers;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/outliner/arraytypes/OutlinesWithInterfaceArrayTypeArguments.java b/src/test/java/com/android/tools/r8/ir/optimize/outliner/arraytypes/OutlinesWithInterfaceArrayTypeArguments.java
index 7b45ad7..01115a3 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/outliner/arraytypes/OutlinesWithInterfaceArrayTypeArguments.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/outliner/arraytypes/OutlinesWithInterfaceArrayTypeArguments.java
@@ -12,12 +12,12 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.CodeMatchers;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/outliner/arraytypes/OutlinesWithPrimitiveArrayTypeArguments.java b/src/test/java/com/android/tools/r8/ir/optimize/outliner/arraytypes/OutlinesWithPrimitiveArrayTypeArguments.java
index 0c50272..7cbe36f 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/outliner/arraytypes/OutlinesWithPrimitiveArrayTypeArguments.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/outliner/arraytypes/OutlinesWithPrimitiveArrayTypeArguments.java
@@ -12,11 +12,11 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.CodeMatchers;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/outliner/b112247415/B112247415.java b/src/test/java/com/android/tools/r8/ir/optimize/outliner/b112247415/B112247415.java
index 2d96946..5822e23 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/outliner/b112247415/B112247415.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/outliner/b112247415/B112247415.java
@@ -12,8 +12,8 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.FoundClassSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/outliner/b133215941/B133215941.java b/src/test/java/com/android/tools/r8/ir/optimize/outliner/b133215941/B133215941.java
index 8692050..f9e415d 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/outliner/b133215941/B133215941.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/outliner/b133215941/B133215941.java
@@ -16,11 +16,11 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ir.optimize.outliner.b133215941.B133215941.TestClass.ClassWithStaticMethod;
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.CodeMatchers;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/outliner/classtypes/B134462736.java b/src/test/java/com/android/tools/r8/ir/optimize/outliner/classtypes/B134462736.java
index c3dd26a..20405de 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/outliner/classtypes/B134462736.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/outliner/classtypes/B134462736.java
@@ -14,11 +14,11 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.CodeMatchers;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import org.junit.Test;
 import org.junit.runner.RunWith;
@@ -115,4 +115,4 @@
       instance.method2(new StringBuilder(), "1", "2");
     }
   }
-}
\ No newline at end of file
+}
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/outliner/primitivetypes/PrimitiveTypesTest.java b/src/test/java/com/android/tools/r8/ir/optimize/outliner/primitivetypes/PrimitiveTypesTest.java
index 56b33d6..9b98601 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/outliner/primitivetypes/PrimitiveTypesTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/outliner/primitivetypes/PrimitiveTypesTest.java
@@ -14,12 +14,12 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.CodeMatchers;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/redundantarraygetelimination/RedundantArrayGetEliminationTest.java b/src/test/java/com/android/tools/r8/ir/optimize/redundantarraygetelimination/RedundantArrayGetEliminationTest.java
index 31eb68f..61f6750 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/redundantarraygetelimination/RedundantArrayGetEliminationTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/redundantarraygetelimination/RedundantArrayGetEliminationTest.java
@@ -9,11 +9,11 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/redundantarraygetelimination/RedundantArrayGetEliminationWithThrowingArrayAccessTest.java b/src/test/java/com/android/tools/r8/ir/optimize/redundantarraygetelimination/RedundantArrayGetEliminationWithThrowingArrayAccessTest.java
index de5ba07..fb3f6c2 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/redundantarraygetelimination/RedundantArrayGetEliminationWithThrowingArrayAccessTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/redundantarraygetelimination/RedundantArrayGetEliminationWithThrowingArrayAccessTest.java
@@ -12,12 +12,12 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FieldSubject;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/redundantcatchrethrowelimination/RedundantCatchRethrowEliminationTest.java b/src/test/java/com/android/tools/r8/ir/optimize/redundantcatchrethrowelimination/RedundantCatchRethrowEliminationTest.java
index 7bd798b..be25526 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/redundantcatchrethrowelimination/RedundantCatchRethrowEliminationTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/redundantcatchrethrowelimination/RedundantCatchRethrowEliminationTest.java
@@ -12,10 +12,10 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/reflection/ForNameTest.java b/src/test/java/com/android/tools/r8/ir/optimize/reflection/ForNameTest.java
index 00121a7..cc38a92 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/reflection/ForNameTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/reflection/ForNameTest.java
@@ -13,10 +13,10 @@
 import com.android.tools.r8.SingleTestRunResult;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/reflection/GetClassBaseAndSubTest.java b/src/test/java/com/android/tools/r8/ir/optimize/reflection/GetClassBaseAndSubTest.java
index db24996..406ffba 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/reflection/GetClassBaseAndSubTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/reflection/GetClassBaseAndSubTest.java
@@ -8,8 +8,8 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/reflection/GetClassOnKeptClassTest.java b/src/test/java/com/android/tools/r8/ir/optimize/reflection/GetClassOnKeptClassTest.java
index 31ee955..6e3872c 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/reflection/GetClassOnKeptClassTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/reflection/GetClassOnKeptClassTest.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.concurrent.Callable;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/reflection/GetClassTest.java b/src/test/java/com/android/tools/r8/ir/optimize/reflection/GetClassTest.java
index bf63725..27eeb13 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/reflection/GetClassTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/reflection/GetClassTest.java
@@ -15,10 +15,10 @@
 import com.android.tools.r8.NoHorizontalClassMerging;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.utils.ListUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/reflection/GetNameTest.java b/src/test/java/com/android/tools/r8/ir/optimize/reflection/GetNameTest.java
index dbee197..e14988f 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/reflection/GetNameTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/reflection/GetNameTest.java
@@ -16,11 +16,11 @@
 import com.android.tools.r8.SingleTestRunResult;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.ToolHelper;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FoundMethodSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Path;
 import java.util.Collection;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/reflection/GetSimpleNameTest.java b/src/test/java/com/android/tools/r8/ir/optimize/reflection/GetSimpleNameTest.java
index aa4ae93..e021325 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/reflection/GetSimpleNameTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/reflection/GetSimpleNameTest.java
@@ -15,10 +15,10 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.ir.optimize.reflection.Outer.TestHelper;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.lang.reflect.Array;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/reflection/InnerClassNameTestRunner.java b/src/test/java/com/android/tools/r8/ir/optimize/reflection/InnerClassNameTestRunner.java
index be144ab..152fe7a 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/reflection/InnerClassNameTestRunner.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/reflection/InnerClassNameTestRunner.java
@@ -16,11 +16,11 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.ToolHelper.DexVm;
-import com.android.tools.r8.utils.internal.BooleanUtils;
 import com.android.tools.r8.utils.DescriptorUtils;
 import com.android.tools.r8.utils.InternalOptions;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import java.util.Collection;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/staticizer/ClassStaticizerTest.java b/src/test/java/com/android/tools/r8/ir/optimize/staticizer/ClassStaticizerTest.java
index 864b64b..7a7da86 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/staticizer/ClassStaticizerTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/staticizer/ClassStaticizerTest.java
@@ -53,9 +53,9 @@
 import com.android.tools.r8.ir.optimize.staticizer.trivial.TrivialTestClass;
 import com.android.tools.r8.naming.MemberNaming.MethodSignature;
 import com.android.tools.r8.utils.InternalOptions;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.Lists;
 import com.google.common.collect.Streams;
 import java.io.IOException;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/string/B370217723Test.java b/src/test/java/com/android/tools/r8/ir/optimize/string/B370217723Test.java
index fb42612..194b074 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/string/B370217723Test.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/string/B370217723Test.java
@@ -6,7 +6,6 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/string/NameThenLengthTest.java b/src/test/java/com/android/tools/r8/ir/optimize/string/NameThenLengthTest.java
index 0427b51..cf834a7 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/string/NameThenLengthTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/string/NameThenLengthTest.java
@@ -18,11 +18,11 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.graph.DexMethod;
 import com.android.tools.r8.utils.InternalOptions;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/string/NestedStringBuilderTest.java b/src/test/java/com/android/tools/r8/ir/optimize/string/NestedStringBuilderTest.java
index 8fdab3d..539ac13 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/string/NestedStringBuilderTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/string/NestedStringBuilderTest.java
@@ -8,9 +8,9 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
@@ -60,4 +60,4 @@
       return one + two;
     }
   }
-}
\ No newline at end of file
+}
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/string/StringBuilderTests.java b/src/test/java/com/android/tools/r8/ir/optimize/string/StringBuilderTests.java
index 04b2b4a..232bbd3 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/string/StringBuilderTests.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/string/StringBuilderTests.java
@@ -12,10 +12,10 @@
 import com.android.tools.r8.R8TestCompileResult;
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeMatchers;
 import com.android.tools.r8.utils.codeinspector.FoundMethodSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.lang.reflect.Method;
 import java.util.List;
 import java.util.function.Function;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/string/StringBuilderWithCharConversionTest.java b/src/test/java/com/android/tools/r8/ir/optimize/string/StringBuilderWithCharConversionTest.java
index b83eb50..82adfb8 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/string/StringBuilderWithCharConversionTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/string/StringBuilderWithCharConversionTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/string/StringBuilderWithEscapingAliasTest.java b/src/test/java/com/android/tools/r8/ir/optimize/string/StringBuilderWithEscapingAliasTest.java
index 9a07555..25a2326 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/string/StringBuilderWithEscapingAliasTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/string/StringBuilderWithEscapingAliasTest.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.Sets;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/string/StringConcatenationTest.java b/src/test/java/com/android/tools/r8/ir/optimize/string/StringConcatenationTest.java
index 99759b2..d155e29 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/string/StringConcatenationTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/string/StringConcatenationTest.java
@@ -14,11 +14,11 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject.JumboStringMode;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/string/StringContentCheckTest.java b/src/test/java/com/android/tools/r8/ir/optimize/string/StringContentCheckTest.java
index 7db3a51..80a427f 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/string/StringContentCheckTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/string/StringContentCheckTest.java
@@ -14,10 +14,10 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.graph.DexMethod;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/string/StringFormatTest.java b/src/test/java/com/android/tools/r8/ir/optimize/string/StringFormatTest.java
index a860dfe..31cdfaa 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/string/StringFormatTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/string/StringFormatTest.java
@@ -12,12 +12,12 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.InvokeInstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.UnsupportedEncodingException;
 import java.util.Formattable;
 import java.util.Formatter;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/string/StringHashCodeTest.java b/src/test/java/com/android/tools/r8/ir/optimize/string/StringHashCodeTest.java
index 6be906c..10f724e 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/string/StringHashCodeTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/string/StringHashCodeTest.java
@@ -14,11 +14,11 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/string/StringIsEmptyTest.java b/src/test/java/com/android/tools/r8/ir/optimize/string/StringIsEmptyTest.java
index a1de3e7..93cefa1 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/string/StringIsEmptyTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/string/StringIsEmptyTest.java
@@ -14,10 +14,10 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/string/StringLengthTest.java b/src/test/java/com/android/tools/r8/ir/optimize/string/StringLengthTest.java
index 656c54a..7030f6f 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/string/StringLengthTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/string/StringLengthTest.java
@@ -15,11 +15,11 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.PrintStream;
 import java.io.UnsupportedEncodingException;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/string/StringToStringTest.java b/src/test/java/com/android/tools/r8/ir/optimize/string/StringToStringTest.java
index 8287ffb..aa16a14 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/string/StringToStringTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/string/StringToStringTest.java
@@ -15,10 +15,10 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.graph.DexMethod;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/string/StringValueOfTest.java b/src/test/java/com/android/tools/r8/ir/optimize/string/StringValueOfTest.java
index 9cb680b..225a3de 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/string/StringValueOfTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/string/StringValueOfTest.java
@@ -17,12 +17,12 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ir.optimize.string.StringValueOfTest.TestClass.Foo;
 import com.android.tools.r8.utils.InternalOptions;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject.JumboStringMode;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/switches/B135542760.java b/src/test/java/com/android/tools/r8/ir/optimize/switches/B135542760.java
index 810baae..823a493 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/switches/B135542760.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/switches/B135542760.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/switches/SwitchCaseRemovalTest.java b/src/test/java/com/android/tools/r8/ir/optimize/switches/SwitchCaseRemovalTest.java
index 319f2f0..b04d6fc 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/switches/SwitchCaseRemovalTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/switches/SwitchCaseRemovalTest.java
@@ -17,11 +17,11 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ir.code.IRCode;
 import com.android.tools.r8.ir.code.Instruction;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Streams;
 import java.util.Set;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/switches/SwitchMapWithMissingFieldTest.java b/src/test/java/com/android/tools/r8/ir/optimize/switches/SwitchMapWithMissingFieldTest.java
index 7cfab4c..f89549e 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/switches/SwitchMapWithMissingFieldTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/switches/SwitchMapWithMissingFieldTest.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.references.ClassReference;
 import com.android.tools.r8.references.Reference;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.File;
 import java.io.IOException;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/switches/SwitchMapWithUnexpectedFieldTest.java b/src/test/java/com/android/tools/r8/ir/optimize/switches/SwitchMapWithUnexpectedFieldTest.java
index 071b8ce..3c6a42c 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/switches/SwitchMapWithUnexpectedFieldTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/switches/SwitchMapWithUnexpectedFieldTest.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.references.ClassReference;
 import com.android.tools.r8.references.Reference;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.File;
 import java.io.IOException;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/templates/GenerateCfUtilityMethodsForCodeOptimizations.java b/src/test/java/com/android/tools/r8/ir/optimize/templates/GenerateCfUtilityMethodsForCodeOptimizations.java
index aa73357..8ddd77d 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/templates/GenerateCfUtilityMethodsForCodeOptimizations.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/templates/GenerateCfUtilityMethodsForCodeOptimizations.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.ToolHelper.TestDataSourceSet;
 import com.android.tools.r8.cfmethodgeneration.MethodGenerationBase;
 import com.android.tools.r8.graph.DexType;
-import com.android.tools.r8.utils.FileUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.charset.StandardCharsets;
 import java.util.ArrayList;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/uninstantiatedtypes/InterfaceMethodTest.java b/src/test/java/com/android/tools/r8/ir/optimize/uninstantiatedtypes/InterfaceMethodTest.java
index bfd7d91..8cb73e9 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/uninstantiatedtypes/InterfaceMethodTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/uninstantiatedtypes/InterfaceMethodTest.java
@@ -15,10 +15,10 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/uninstantiatedtypes/InvokeMethodWithNonNullParamCheckTest.java b/src/test/java/com/android/tools/r8/ir/optimize/uninstantiatedtypes/InvokeMethodWithNonNullParamCheckTest.java
index c7729f4..59f8c3d 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/uninstantiatedtypes/InvokeMethodWithNonNullParamCheckTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/uninstantiatedtypes/InvokeMethodWithNonNullParamCheckTest.java
@@ -13,11 +13,11 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FoundMethodSubject;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Streams;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/uninstantiatedtypes/InvokeMethodWithReceiverOptimizationTest.java b/src/test/java/com/android/tools/r8/ir/optimize/uninstantiatedtypes/InvokeMethodWithReceiverOptimizationTest.java
index b54c77a..6c30be3 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/uninstantiatedtypes/InvokeMethodWithReceiverOptimizationTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/uninstantiatedtypes/InvokeMethodWithReceiverOptimizationTest.java
@@ -13,12 +13,12 @@
 import com.android.tools.r8.NeverInline;
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FoundMethodSubject;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.Streams;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/uninstantiatedtypes/LambdaInstantiatedTypeTest.java b/src/test/java/com/android/tools/r8/ir/optimize/uninstantiatedtypes/LambdaInstantiatedTypeTest.java
index d07bff5..d51f5b5 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/uninstantiatedtypes/LambdaInstantiatedTypeTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/uninstantiatedtypes/LambdaInstantiatedTypeTest.java
@@ -10,9 +10,9 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/uninstantiatedtypes/NestedInterfaceMethodTest.java b/src/test/java/com/android/tools/r8/ir/optimize/uninstantiatedtypes/NestedInterfaceMethodTest.java
index e90e867..d1808bc 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/uninstantiatedtypes/NestedInterfaceMethodTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/uninstantiatedtypes/NestedInterfaceMethodTest.java
@@ -15,10 +15,10 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/uninstantiatedtypes/ParameterRewritingTest.java b/src/test/java/com/android/tools/r8/ir/optimize/uninstantiatedtypes/ParameterRewritingTest.java
index 9da3ee6..eb7a5c8 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/uninstantiatedtypes/ParameterRewritingTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/uninstantiatedtypes/ParameterRewritingTest.java
@@ -14,10 +14,10 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.graph.DexMethod;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/uninstantiatedtypes/PrivateInstanceMethodCollisionTest.java b/src/test/java/com/android/tools/r8/ir/optimize/uninstantiatedtypes/PrivateInstanceMethodCollisionTest.java
index 7f956c6..3ba1244 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/uninstantiatedtypes/PrivateInstanceMethodCollisionTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/uninstantiatedtypes/PrivateInstanceMethodCollisionTest.java
@@ -15,12 +15,12 @@
 import com.android.tools.r8.NoMethodStaticizing;
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FoundMethodSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/uninstantiatedtypes/SynchronizedMethodTest.java b/src/test/java/com/android/tools/r8/ir/optimize/uninstantiatedtypes/SynchronizedMethodTest.java
index 2f529fc..81745be 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/uninstantiatedtypes/SynchronizedMethodTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/uninstantiatedtypes/SynchronizedMethodTest.java
@@ -14,12 +14,12 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.stream.Collectors;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/uninstantiatedtypes/UninstantiatedAnnotatedArgumentsTest.java b/src/test/java/com/android/tools/r8/ir/optimize/uninstantiatedtypes/UninstantiatedAnnotatedArgumentsTest.java
index c7deb66..403b9fa 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/uninstantiatedtypes/UninstantiatedAnnotatedArgumentsTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/uninstantiatedtypes/UninstantiatedAnnotatedArgumentsTest.java
@@ -17,11 +17,11 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.graph.DexAnnotation;
 import com.android.tools.r8.graph.DexAnnotationSet;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import com.google.common.collect.ImmutableList;
 import java.lang.annotation.ElementType;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/uninstantiatedtypes/VoidReturnTypeRewritingTest.java b/src/test/java/com/android/tools/r8/ir/optimize/uninstantiatedtypes/VoidReturnTypeRewritingTest.java
index 1911b14..71a2e1f 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/uninstantiatedtypes/VoidReturnTypeRewritingTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/uninstantiatedtypes/VoidReturnTypeRewritingTest.java
@@ -15,10 +15,10 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/unsafe/GenerateSyntheticUnsafeMethods.java b/src/test/java/com/android/tools/r8/ir/optimize/unsafe/GenerateSyntheticUnsafeMethods.java
index 3cf3007..6ab370d 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/unsafe/GenerateSyntheticUnsafeMethods.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/unsafe/GenerateSyntheticUnsafeMethods.java
@@ -19,7 +19,7 @@
 import com.android.tools.r8.graph.DexTypeList;
 import com.android.tools.r8.ir.optimize.unsafe.SyntheticUnsafeMethodTemplates.UnsafeStub;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.FileUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import java.nio.charset.StandardCharsets;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/unusedarguments/CollisionWithLibraryMethodsTest.java b/src/test/java/com/android/tools/r8/ir/optimize/unusedarguments/CollisionWithLibraryMethodsTest.java
index 01cb4c8..92be064 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/unusedarguments/CollisionWithLibraryMethodsTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/unusedarguments/CollisionWithLibraryMethodsTest.java
@@ -14,12 +14,12 @@
 import com.android.tools.r8.NoMethodStaticizing;
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FoundMethodSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/unusedarguments/CollisionWithUnusedArgumentAndParameterAnnotationsTest.java b/src/test/java/com/android/tools/r8/ir/optimize/unusedarguments/CollisionWithUnusedArgumentAndParameterAnnotationsTest.java
index 4ea3d94..a82db49 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/unusedarguments/CollisionWithUnusedArgumentAndParameterAnnotationsTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/unusedarguments/CollisionWithUnusedArgumentAndParameterAnnotationsTest.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/unusedarguments/PrivateInstanceMethodCollisionTest.java b/src/test/java/com/android/tools/r8/ir/optimize/unusedarguments/PrivateInstanceMethodCollisionTest.java
index fd3c091..962cace 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/unusedarguments/PrivateInstanceMethodCollisionTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/unusedarguments/PrivateInstanceMethodCollisionTest.java
@@ -15,12 +15,12 @@
 import com.android.tools.r8.NoMethodStaticizing;
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FoundMethodSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/unusedarguments/UnusedAnnotatedArgumentsTest.java b/src/test/java/com/android/tools/r8/ir/optimize/unusedarguments/UnusedAnnotatedArgumentsTest.java
index 234b194..f56923e 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/unusedarguments/UnusedAnnotatedArgumentsTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/unusedarguments/UnusedAnnotatedArgumentsTest.java
@@ -16,11 +16,11 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.graph.DexAnnotation;
 import com.android.tools.r8.graph.DexAnnotationSet;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import com.google.common.collect.ImmutableList;
 import java.lang.annotation.ElementType;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/unusedarguments/UnusedAnnotatedArgumentsWithMissingAnnotationsTest.java b/src/test/java/com/android/tools/r8/ir/optimize/unusedarguments/UnusedAnnotatedArgumentsWithMissingAnnotationsTest.java
index 8aafe6f..c77cf24 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/unusedarguments/UnusedAnnotatedArgumentsWithMissingAnnotationsTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/unusedarguments/UnusedAnnotatedArgumentsWithMissingAnnotationsTest.java
@@ -11,10 +11,10 @@
 
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/unusedarguments/UnusedArgumentRemovalWithOverridingTest.java b/src/test/java/com/android/tools/r8/ir/optimize/unusedarguments/UnusedArgumentRemovalWithOverridingTest.java
index e61ac03..b56de4e 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/unusedarguments/UnusedArgumentRemovalWithOverridingTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/unusedarguments/UnusedArgumentRemovalWithOverridingTest.java
@@ -13,11 +13,11 @@
 import com.android.tools.r8.NoVerticalClassMerging;
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/unusedarguments/UnusedArgumentsCollisionMappingTest.java b/src/test/java/com/android/tools/r8/ir/optimize/unusedarguments/UnusedArgumentsCollisionMappingTest.java
index 77d917b..abe246d 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/unusedarguments/UnusedArgumentsCollisionMappingTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/unusedarguments/UnusedArgumentsCollisionMappingTest.java
@@ -15,10 +15,10 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FoundMethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/unusedarguments/UnusedArgumentsCollisionTest.java b/src/test/java/com/android/tools/r8/ir/optimize/unusedarguments/UnusedArgumentsCollisionTest.java
index 0c86367..7521ff0 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/unusedarguments/UnusedArgumentsCollisionTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/unusedarguments/UnusedArgumentsCollisionTest.java
@@ -15,12 +15,12 @@
 import com.android.tools.r8.NoVerticalClassMerging;
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FoundMethodSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/unusedarguments/UnusedArgumentsInstanceConstructorCollisionTest.java b/src/test/java/com/android/tools/r8/ir/optimize/unusedarguments/UnusedArgumentsInstanceConstructorCollisionTest.java
index 557eb17..0bb0724 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/unusedarguments/UnusedArgumentsInstanceConstructorCollisionTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/unusedarguments/UnusedArgumentsInstanceConstructorCollisionTest.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/unusedarguments/UnusedArgumentsInstanceConstructorTest.java b/src/test/java/com/android/tools/r8/ir/optimize/unusedarguments/UnusedArgumentsInstanceConstructorTest.java
index 0e5b15d..9aedd4b 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/unusedarguments/UnusedArgumentsInstanceConstructorTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/unusedarguments/UnusedArgumentsInstanceConstructorTest.java
@@ -15,11 +15,11 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.HorizontallyMergedClassesInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/ir/optimize/unusedinterfaces/UnusedButKeptInterfaceTest.java b/src/test/java/com/android/tools/r8/ir/optimize/unusedinterfaces/UnusedButKeptInterfaceTest.java
index 21f61ce..5b8d5b6 100644
--- a/src/test/java/com/android/tools/r8/ir/optimize/unusedinterfaces/UnusedButKeptInterfaceTest.java
+++ b/src/test/java/com/android/tools/r8/ir/optimize/unusedinterfaces/UnusedButKeptInterfaceTest.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/jacoco/JacocoClasses.java b/src/test/java/com/android/tools/r8/jacoco/JacocoClasses.java
index 3a58eeb..d9a0889 100644
--- a/src/test/java/com/android/tools/r8/jacoco/JacocoClasses.java
+++ b/src/test/java/com/android/tools/r8/jacoco/JacocoClasses.java
@@ -5,8 +5,8 @@
 
 import static com.android.tools.r8.utils.CfUtils.extractClassName;
 import static com.android.tools.r8.utils.DescriptorUtils.JAVA_PACKAGE_SEPARATOR;
-import static com.android.tools.r8.utils.FileUtils.CLASS_EXTENSION;
-import static com.android.tools.r8.utils.FileUtils.JAR_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.CLASS_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.JAR_EXTENSION;
 import static org.junit.Assert.assertEquals;
 
 import com.android.tools.r8.ToolHelper;
diff --git a/src/test/java/com/android/tools/r8/jasmin/InvalidDebugInfoTests.java b/src/test/java/com/android/tools/r8/jasmin/InvalidDebugInfoTests.java
index 8a36a1c..8115bb3 100644
--- a/src/test/java/com/android/tools/r8/jasmin/InvalidDebugInfoTests.java
+++ b/src/test/java/com/android/tools/r8/jasmin/InvalidDebugInfoTests.java
@@ -14,9 +14,9 @@
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.jasmin.JasminBuilder.ClassFileVersion;
 import com.android.tools.r8.naming.MemberNaming.MethodSignature;
-import com.android.tools.r8.utils.internal.BooleanUtils;
 import com.android.tools.r8.utils.InternalOptions;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/jasmin/NameTestBase.java b/src/test/java/com/android/tools/r8/jasmin/NameTestBase.java
index 0b335a9..db02778 100644
--- a/src/test/java/com/android/tools/r8/jasmin/NameTestBase.java
+++ b/src/test/java/com/android/tools/r8/jasmin/NameTestBase.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.CompilationFailedException;
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.InvalidPathException;
 import java.util.Arrays;
 import java.util.Collection;
diff --git a/src/test/java/com/android/tools/r8/keepanno/AnnotationPatternAnyRetentionTest.java b/src/test/java/com/android/tools/r8/keepanno/AnnotationPatternAnyRetentionTest.java
index dea3f0a..bd3cfac 100644
--- a/src/test/java/com/android/tools/r8/keepanno/AnnotationPatternAnyRetentionTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/AnnotationPatternAnyRetentionTest.java
@@ -13,9 +13,9 @@
 import com.android.tools.r8.keepanno.annotations.KeepTarget;
 import com.android.tools.r8.keepanno.annotations.UsedByReflection;
 import com.android.tools.r8.keepanno.annotations.UsesReflection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
diff --git a/src/test/java/com/android/tools/r8/keepanno/AnnotationPatternClassRetentionTest.java b/src/test/java/com/android/tools/r8/keepanno/AnnotationPatternClassRetentionTest.java
index 860f1bb..b0fcd9e 100644
--- a/src/test/java/com/android/tools/r8/keepanno/AnnotationPatternClassRetentionTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/AnnotationPatternClassRetentionTest.java
@@ -14,9 +14,9 @@
 import com.android.tools.r8.keepanno.annotations.KeepTarget;
 import com.android.tools.r8.keepanno.annotations.UsedByReflection;
 import com.android.tools.r8.keepanno.annotations.UsesReflection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
diff --git a/src/test/java/com/android/tools/r8/keepanno/AnnotationPatternMultipleTest.java b/src/test/java/com/android/tools/r8/keepanno/AnnotationPatternMultipleTest.java
index bc8a3a7..5b3d602 100644
--- a/src/test/java/com/android/tools/r8/keepanno/AnnotationPatternMultipleTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/AnnotationPatternMultipleTest.java
@@ -15,9 +15,9 @@
 import com.android.tools.r8.keepanno.annotations.KeepTarget;
 import com.android.tools.r8.keepanno.annotations.UsedByReflection;
 import com.android.tools.r8.keepanno.annotations.UsesReflection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
diff --git a/src/test/java/com/android/tools/r8/keepanno/ArrayPatternsTest.java b/src/test/java/com/android/tools/r8/keepanno/ArrayPatternsTest.java
index d37eb76..8dd15d9 100644
--- a/src/test/java/com/android/tools/r8/keepanno/ArrayPatternsTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/ArrayPatternsTest.java
@@ -13,8 +13,8 @@
 import com.android.tools.r8.keepanno.annotations.TypePattern;
 import com.android.tools.r8.keepanno.annotations.UsedByReflection;
 import com.android.tools.r8.keepanno.annotations.UsesReflection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.Arrays;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/keepanno/CheckOptimizedOutAnnotationTest.java b/src/test/java/com/android/tools/r8/keepanno/CheckOptimizedOutAnnotationTest.java
index 09b5f3a..254dca0 100644
--- a/src/test/java/com/android/tools/r8/keepanno/CheckOptimizedOutAnnotationTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/CheckOptimizedOutAnnotationTest.java
@@ -20,8 +20,8 @@
 import com.android.tools.r8.TestDiagnosticMessages;
 import com.android.tools.r8.errors.CheckDiscardDiagnostic;
 import com.android.tools.r8.keepanno.annotations.CheckOptimizedOut;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/keepanno/CheckRemovedAnnotationTest.java b/src/test/java/com/android/tools/r8/keepanno/CheckRemovedAnnotationTest.java
index f330234..82efbfe 100644
--- a/src/test/java/com/android/tools/r8/keepanno/CheckRemovedAnnotationTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/CheckRemovedAnnotationTest.java
@@ -20,8 +20,8 @@
 import com.android.tools.r8.TestDiagnosticMessages;
 import com.android.tools.r8.errors.CheckDiscardDiagnostic;
 import com.android.tools.r8.keepanno.annotations.CheckRemoved;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/keepanno/ClassAnnotatedByAnyAnnoConstraintPatternTest.java b/src/test/java/com/android/tools/r8/keepanno/ClassAnnotatedByAnyAnnoConstraintPatternTest.java
index c1db6c8..7f3b41b 100644
--- a/src/test/java/com/android/tools/r8/keepanno/ClassAnnotatedByAnyAnnoConstraintPatternTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/ClassAnnotatedByAnyAnnoConstraintPatternTest.java
@@ -15,8 +15,8 @@
 import com.android.tools.r8.keepanno.annotations.KeepTarget;
 import com.android.tools.r8.keepanno.annotations.UsedByReflection;
 import com.android.tools.r8.keepanno.annotations.UsesReflection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
diff --git a/src/test/java/com/android/tools/r8/keepanno/ClassAnnotatedByAnyAnnoPatternTest.java b/src/test/java/com/android/tools/r8/keepanno/ClassAnnotatedByAnyAnnoPatternTest.java
index 79566db..c33189f 100644
--- a/src/test/java/com/android/tools/r8/keepanno/ClassAnnotatedByAnyAnnoPatternTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/ClassAnnotatedByAnyAnnoPatternTest.java
@@ -14,8 +14,8 @@
 import com.android.tools.r8.keepanno.annotations.KeepTarget;
 import com.android.tools.r8.keepanno.annotations.UsedByReflection;
 import com.android.tools.r8.keepanno.annotations.UsesReflection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
diff --git a/src/test/java/com/android/tools/r8/keepanno/ClassAnnotatedByPatternsTest.java b/src/test/java/com/android/tools/r8/keepanno/ClassAnnotatedByPatternsTest.java
index 67fbdae..4f823a1 100644
--- a/src/test/java/com/android/tools/r8/keepanno/ClassAnnotatedByPatternsTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/ClassAnnotatedByPatternsTest.java
@@ -14,8 +14,8 @@
 import com.android.tools.r8.keepanno.annotations.KeepTarget;
 import com.android.tools.r8.keepanno.annotations.UsedByReflection;
 import com.android.tools.r8.keepanno.annotations.UsesReflection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
diff --git a/src/test/java/com/android/tools/r8/keepanno/ClassAnnotatedBySingleAnnotationTest.java b/src/test/java/com/android/tools/r8/keepanno/ClassAnnotatedBySingleAnnotationTest.java
index b545044..01c50c0 100644
--- a/src/test/java/com/android/tools/r8/keepanno/ClassAnnotatedBySingleAnnotationTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/ClassAnnotatedBySingleAnnotationTest.java
@@ -15,9 +15,9 @@
 import com.android.tools.r8.keepanno.annotations.KeepTarget;
 import com.android.tools.r8.keepanno.annotations.UsedByReflection;
 import com.android.tools.r8.keepanno.annotations.UsesReflection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
diff --git a/src/test/java/com/android/tools/r8/keepanno/ClassNameStringPatternsTest.java b/src/test/java/com/android/tools/r8/keepanno/ClassNameStringPatternsTest.java
index 8961217..4afb423 100644
--- a/src/test/java/com/android/tools/r8/keepanno/ClassNameStringPatternsTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/ClassNameStringPatternsTest.java
@@ -15,9 +15,9 @@
 import com.android.tools.r8.keepanno.annotations.TypePattern;
 import com.android.tools.r8.keepanno.annotations.UsedByReflection;
 import com.android.tools.r8.keepanno.annotations.UsesReflection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.lang.reflect.Method;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/keepanno/FieldNameStringPatternsTest.java b/src/test/java/com/android/tools/r8/keepanno/FieldNameStringPatternsTest.java
index fafbe72..104fef0 100644
--- a/src/test/java/com/android/tools/r8/keepanno/FieldNameStringPatternsTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/FieldNameStringPatternsTest.java
@@ -13,8 +13,8 @@
 import com.android.tools.r8.keepanno.annotations.StringPattern;
 import com.android.tools.r8.keepanno.annotations.UsedByReflection;
 import com.android.tools.r8.keepanno.annotations.UsesReflection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.lang.reflect.Field;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/keepanno/FieldPatternsTest.java b/src/test/java/com/android/tools/r8/keepanno/FieldPatternsTest.java
index 8cea2b6..c378631 100644
--- a/src/test/java/com/android/tools/r8/keepanno/FieldPatternsTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/FieldPatternsTest.java
@@ -11,8 +11,8 @@
 import com.android.tools.r8.keepanno.annotations.KeepTarget;
 import com.android.tools.r8.keepanno.annotations.TypePattern;
 import com.android.tools.r8.keepanno.annotations.UsesReflection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.lang.reflect.Field;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/keepanno/KeepAccessVisibilityFlagsTest.java b/src/test/java/com/android/tools/r8/keepanno/KeepAccessVisibilityFlagsTest.java
index f15c973..7518819 100644
--- a/src/test/java/com/android/tools/r8/keepanno/KeepAccessVisibilityFlagsTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/KeepAccessVisibilityFlagsTest.java
@@ -14,9 +14,9 @@
 import com.android.tools.r8.keepanno.annotations.MemberAccessFlags;
 import com.android.tools.r8.keepanno.annotations.MethodAccessFlags;
 import com.android.tools.r8.keepanno.annotations.UsesReflection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 import java.lang.reflect.Field;
diff --git a/src/test/java/com/android/tools/r8/keepanno/KeepAnnoInstanceOfTargetTest.java b/src/test/java/com/android/tools/r8/keepanno/KeepAnnoInstanceOfTargetTest.java
index abf727f..9ad9179 100644
--- a/src/test/java/com/android/tools/r8/keepanno/KeepAnnoInstanceOfTargetTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/KeepAnnoInstanceOfTargetTest.java
@@ -8,7 +8,7 @@
 
 import com.android.tools.r8.keepanno.annotations.KeepTarget;
 import com.android.tools.r8.keepanno.annotations.UsesReflection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/keepanno/KeepAnnoTestBuilder.java b/src/test/java/com/android/tools/r8/keepanno/KeepAnnoTestBuilder.java
index 404cfe0..895049a 100644
--- a/src/test/java/com/android/tools/r8/keepanno/KeepAnnoTestBuilder.java
+++ b/src/test/java/com/android/tools/r8/keepanno/KeepAnnoTestBuilder.java
@@ -5,10 +5,10 @@
 package com.android.tools.r8.keepanno;
 
 import static com.android.tools.r8.R8TestBuilder.KeepAnnotationLibrary.ANDROIDX;
-import static com.android.tools.r8.utils.FileUtils.isClassFile;
-import static com.android.tools.r8.utils.FileUtils.isJarFile;
-import static com.android.tools.r8.utils.FileUtils.isKotlinBuiltinsFile;
-import static com.android.tools.r8.utils.FileUtils.isZipFile;
+import static com.android.tools.r8.utils.internal.FileUtils.isClassFile;
+import static com.android.tools.r8.utils.internal.FileUtils.isJarFile;
+import static com.android.tools.r8.utils.internal.FileUtils.isKotlinBuiltinsFile;
+import static com.android.tools.r8.utils.internal.FileUtils.isZipFile;
 
 import com.android.tools.r8.DataEntryResource;
 import com.android.tools.r8.ExternalR8TestBuilder;
diff --git a/src/test/java/com/android/tools/r8/keepanno/KeepAnnoWithWhyAreYouKeepingTest.java b/src/test/java/com/android/tools/r8/keepanno/KeepAnnoWithWhyAreYouKeepingTest.java
index 25ddd75..5b8d7bd 100644
--- a/src/test/java/com/android/tools/r8/keepanno/KeepAnnoWithWhyAreYouKeepingTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/KeepAnnoWithWhyAreYouKeepingTest.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.keepanno.annotations.KeepItemKind;
 import com.android.tools.r8.keepanno.annotations.KeepTarget;
 import com.android.tools.r8.keepanno.annotations.UsesReflection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/keepanno/KeepAnnotationViaSuperTest.java b/src/test/java/com/android/tools/r8/keepanno/KeepAnnotationViaSuperTest.java
index 3412fc4..263de90 100644
--- a/src/test/java/com/android/tools/r8/keepanno/KeepAnnotationViaSuperTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/KeepAnnotationViaSuperTest.java
@@ -12,9 +12,9 @@
 import com.android.tools.r8.keepanno.annotations.InstanceOfPattern;
 import com.android.tools.r8.keepanno.annotations.KeepTarget;
 import com.android.tools.r8.keepanno.annotations.UsesReflection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
diff --git a/src/test/java/com/android/tools/r8/keepanno/KeepBindingTest.java b/src/test/java/com/android/tools/r8/keepanno/KeepBindingTest.java
index a58376c..044126b 100644
--- a/src/test/java/com/android/tools/r8/keepanno/KeepBindingTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/KeepBindingTest.java
@@ -11,8 +11,8 @@
 import com.android.tools.r8.keepanno.annotations.KeepCondition;
 import com.android.tools.r8.keepanno.annotations.KeepEdge;
 import com.android.tools.r8.keepanno.annotations.KeepTarget;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/keepanno/KeepClassApiTest.java b/src/test/java/com/android/tools/r8/keepanno/KeepClassApiTest.java
index 4032911..99adc6d 100644
--- a/src/test/java/com/android/tools/r8/keepanno/KeepClassApiTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/KeepClassApiTest.java
@@ -13,10 +13,10 @@
 
 import com.android.tools.r8.keepanno.annotations.KeepForApi;
 import com.android.tools.r8.keepanno.annotations.MemberAccessFlags;
-import com.android.tools.r8.utils.internal.Box;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.Box;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Path;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/keepanno/KeepConjunctiveBindingsTest.java b/src/test/java/com/android/tools/r8/keepanno/KeepConjunctiveBindingsTest.java
index 41d0b88..a54312e 100644
--- a/src/test/java/com/android/tools/r8/keepanno/KeepConjunctiveBindingsTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/KeepConjunctiveBindingsTest.java
@@ -11,8 +11,8 @@
 import com.android.tools.r8.keepanno.annotations.KeepBinding;
 import com.android.tools.r8.keepanno.annotations.KeepEdge;
 import com.android.tools.r8.keepanno.annotations.KeepTarget;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.lang.reflect.Field;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/keepanno/KeepConjunctiveBindingsWithInlineMembersTest.java b/src/test/java/com/android/tools/r8/keepanno/KeepConjunctiveBindingsWithInlineMembersTest.java
index 57f78cb..93a6b72 100644
--- a/src/test/java/com/android/tools/r8/keepanno/KeepConjunctiveBindingsWithInlineMembersTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/KeepConjunctiveBindingsWithInlineMembersTest.java
@@ -11,8 +11,8 @@
 import com.android.tools.r8.keepanno.annotations.KeepBinding;
 import com.android.tools.r8.keepanno.annotations.KeepEdge;
 import com.android.tools.r8.keepanno.annotations.KeepTarget;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.lang.reflect.Field;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/keepanno/KeepConjunctiveBindingsWithoutHolderTest.java b/src/test/java/com/android/tools/r8/keepanno/KeepConjunctiveBindingsWithoutHolderTest.java
index 3a14be1..1760ca3 100644
--- a/src/test/java/com/android/tools/r8/keepanno/KeepConjunctiveBindingsWithoutHolderTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/KeepConjunctiveBindingsWithoutHolderTest.java
@@ -11,8 +11,8 @@
 import com.android.tools.r8.keepanno.annotations.KeepBinding;
 import com.android.tools.r8.keepanno.annotations.KeepEdge;
 import com.android.tools.r8.keepanno.annotations.KeepTarget;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.lang.reflect.Field;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/keepanno/KeepDisjunctiveConsequencesTest.java b/src/test/java/com/android/tools/r8/keepanno/KeepDisjunctiveConsequencesTest.java
index 77a00b4..f05a11e 100644
--- a/src/test/java/com/android/tools/r8/keepanno/KeepDisjunctiveConsequencesTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/KeepDisjunctiveConsequencesTest.java
@@ -10,8 +10,8 @@
 import com.android.tools.r8.keepanno.annotations.KeepConstraint;
 import com.android.tools.r8.keepanno.annotations.KeepTarget;
 import com.android.tools.r8.keepanno.annotations.UsesReflection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.lang.reflect.Field;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/keepanno/KeepEmptyClassTest.java b/src/test/java/com/android/tools/r8/keepanno/KeepEmptyClassTest.java
index 9ba7ff6..7257fb3 100644
--- a/src/test/java/com/android/tools/r8/keepanno/KeepEmptyClassTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/KeepEmptyClassTest.java
@@ -14,9 +14,9 @@
 import com.android.tools.r8.keepanno.annotations.UsedByReflection;
 import com.android.tools.r8.keepanno.annotations.UsesReflection;
 import com.android.tools.r8.transformers.ClassFileTransformer.MethodPredicate;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/keepanno/KeepFieldValueApiTest.java b/src/test/java/com/android/tools/r8/keepanno/KeepFieldValueApiTest.java
index 61f3496..ed5d477 100644
--- a/src/test/java/com/android/tools/r8/keepanno/KeepFieldValueApiTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/KeepFieldValueApiTest.java
@@ -12,10 +12,10 @@
 import com.android.tools.r8.keepanno.annotations.KeepForApi;
 import com.android.tools.r8.keepanno.annotations.KeepItemKind;
 import com.android.tools.r8.keepanno.annotations.KeepTarget;
-import com.android.tools.r8.utils.internal.Box;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.Box;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Path;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/keepanno/KeepFooIfBarAnyClassTest.java b/src/test/java/com/android/tools/r8/keepanno/KeepFooIfBarAnyClassTest.java
index 9ce1e74..99d3778 100644
--- a/src/test/java/com/android/tools/r8/keepanno/KeepFooIfBarAnyClassTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/KeepFooIfBarAnyClassTest.java
@@ -9,8 +9,8 @@
 import com.android.tools.r8.keepanno.annotations.KeepCondition;
 import com.android.tools.r8.keepanno.annotations.KeepEdge;
 import com.android.tools.r8.keepanno.annotations.KeepTarget;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/keepanno/KeepFooIfBarSameClassTest.java b/src/test/java/com/android/tools/r8/keepanno/KeepFooIfBarSameClassTest.java
index f071c4b..7f6d73c 100644
--- a/src/test/java/com/android/tools/r8/keepanno/KeepFooIfBarSameClassTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/KeepFooIfBarSameClassTest.java
@@ -11,9 +11,9 @@
 import com.android.tools.r8.keepanno.annotations.KeepCondition;
 import com.android.tools.r8.keepanno.annotations.KeepEdge;
 import com.android.tools.r8.keepanno.annotations.KeepTarget;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.Subject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.hamcrest.Matcher;
diff --git a/src/test/java/com/android/tools/r8/keepanno/KeepInclusiveInstanceOfTest.java b/src/test/java/com/android/tools/r8/keepanno/KeepInclusiveInstanceOfTest.java
index d17e742..b8e1651 100644
--- a/src/test/java/com/android/tools/r8/keepanno/KeepInclusiveInstanceOfTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/KeepInclusiveInstanceOfTest.java
@@ -8,7 +8,7 @@
 
 import com.android.tools.r8.keepanno.annotations.KeepTarget;
 import com.android.tools.r8.keepanno.annotations.UsesReflection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/keepanno/KeepMainViaBindingTest.java b/src/test/java/com/android/tools/r8/keepanno/KeepMainViaBindingTest.java
index 607d9c5..008fc19 100644
--- a/src/test/java/com/android/tools/r8/keepanno/KeepMainViaBindingTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/KeepMainViaBindingTest.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.keepanno.annotations.KeepEdge;
 import com.android.tools.r8.keepanno.annotations.KeepItemKind;
 import com.android.tools.r8.keepanno.annotations.KeepTarget;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/keepanno/KeepMembersAccessFlagsTest.java b/src/test/java/com/android/tools/r8/keepanno/KeepMembersAccessFlagsTest.java
index ef96447..dbd4ce1 100644
--- a/src/test/java/com/android/tools/r8/keepanno/KeepMembersAccessFlagsTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/KeepMembersAccessFlagsTest.java
@@ -12,9 +12,9 @@
 import com.android.tools.r8.keepanno.annotations.KeepTarget;
 import com.android.tools.r8.keepanno.annotations.MemberAccessFlags;
 import com.android.tools.r8.keepanno.annotations.UsesReflection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.lang.reflect.Field;
 import java.lang.reflect.Method;
diff --git a/src/test/java/com/android/tools/r8/keepanno/KeepMembersApiTest.java b/src/test/java/com/android/tools/r8/keepanno/KeepMembersApiTest.java
index 3fa0fad..67671b9 100644
--- a/src/test/java/com/android/tools/r8/keepanno/KeepMembersApiTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/KeepMembersApiTest.java
@@ -12,10 +12,10 @@
 
 import com.android.tools.r8.keepanno.annotations.KeepForApi;
 import com.android.tools.r8.keepanno.annotations.KeepItemKind;
-import com.android.tools.r8.utils.internal.Box;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.Box;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Path;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/keepanno/KeepMethodsAccessFlagsTest.java b/src/test/java/com/android/tools/r8/keepanno/KeepMethodsAccessFlagsTest.java
index dd9b5ca..122fc6a 100644
--- a/src/test/java/com/android/tools/r8/keepanno/KeepMethodsAccessFlagsTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/KeepMethodsAccessFlagsTest.java
@@ -11,9 +11,9 @@
 import com.android.tools.r8.keepanno.annotations.KeepTarget;
 import com.android.tools.r8.keepanno.annotations.MethodAccessFlags;
 import com.android.tools.r8.keepanno.annotations.UsesReflection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.lang.reflect.Method;
 import java.lang.reflect.Modifier;
diff --git a/src/test/java/com/android/tools/r8/keepanno/KeepMethodsEmptyAccessFlagsTest.java b/src/test/java/com/android/tools/r8/keepanno/KeepMethodsEmptyAccessFlagsTest.java
index 3140f50..7ccf930 100644
--- a/src/test/java/com/android/tools/r8/keepanno/KeepMethodsEmptyAccessFlagsTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/KeepMethodsEmptyAccessFlagsTest.java
@@ -9,9 +9,9 @@
 import com.android.tools.r8.keepanno.annotations.KeepItemKind;
 import com.android.tools.r8.keepanno.annotations.KeepTarget;
 import com.android.tools.r8.keepanno.annotations.UsesReflection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.lang.reflect.Method;
 import java.lang.reflect.Modifier;
diff --git a/src/test/java/com/android/tools/r8/keepanno/KeepNameAndInstanceOfTest.java b/src/test/java/com/android/tools/r8/keepanno/KeepNameAndInstanceOfTest.java
index e3687c6..833302b 100644
--- a/src/test/java/com/android/tools/r8/keepanno/KeepNameAndInstanceOfTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/KeepNameAndInstanceOfTest.java
@@ -5,7 +5,7 @@
 
 import com.android.tools.r8.keepanno.annotations.KeepTarget;
 import com.android.tools.r8.keepanno.annotations.UsesReflection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/keepanno/KeepSameMethodTest.java b/src/test/java/com/android/tools/r8/keepanno/KeepSameMethodTest.java
index 96670a0..22d59f8 100644
--- a/src/test/java/com/android/tools/r8/keepanno/KeepSameMethodTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/KeepSameMethodTest.java
@@ -13,8 +13,8 @@
 import com.android.tools.r8.keepanno.annotations.KeepEdge;
 import com.android.tools.r8.keepanno.annotations.KeepItemKind;
 import com.android.tools.r8.keepanno.annotations.KeepTarget;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/keepanno/KeepStaticBindingTest.java b/src/test/java/com/android/tools/r8/keepanno/KeepStaticBindingTest.java
index 35b999c..bb92e71 100644
--- a/src/test/java/com/android/tools/r8/keepanno/KeepStaticBindingTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/KeepStaticBindingTest.java
@@ -10,8 +10,8 @@
 import com.android.tools.r8.keepanno.annotations.KeepBinding;
 import com.android.tools.r8.keepanno.annotations.KeepEdge;
 import com.android.tools.r8.keepanno.annotations.KeepTarget;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/keepanno/KeepTargetClassAndMemberKindTest.java b/src/test/java/com/android/tools/r8/keepanno/KeepTargetClassAndMemberKindTest.java
index f02358a..4ef18f3 100644
--- a/src/test/java/com/android/tools/r8/keepanno/KeepTargetClassAndMemberKindTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/KeepTargetClassAndMemberKindTest.java
@@ -10,8 +10,8 @@
 import com.android.tools.r8.keepanno.annotations.KeepItemKind;
 import com.android.tools.r8.keepanno.annotations.KeepTarget;
 import com.android.tools.r8.keepanno.annotations.UsesReflection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/keepanno/KeepTypePatternWithInstanceOfTest.java b/src/test/java/com/android/tools/r8/keepanno/KeepTypePatternWithInstanceOfTest.java
index ee311a5..9ea32b6 100644
--- a/src/test/java/com/android/tools/r8/keepanno/KeepTypePatternWithInstanceOfTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/KeepTypePatternWithInstanceOfTest.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.keepanno.annotations.KeepTarget;
 import com.android.tools.r8.keepanno.annotations.TypePattern;
 import com.android.tools.r8.keepanno.annotations.UsesReflection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/keepanno/KeepUsedByNativeAnnotationTest.java b/src/test/java/com/android/tools/r8/keepanno/KeepUsedByNativeAnnotationTest.java
index 8bf1f75..8f9dcf4 100644
--- a/src/test/java/com/android/tools/r8/keepanno/KeepUsedByNativeAnnotationTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/KeepUsedByNativeAnnotationTest.java
@@ -11,8 +11,8 @@
 import com.android.tools.r8.keepanno.annotations.KeepCondition;
 import com.android.tools.r8.keepanno.annotations.KeepItemKind;
 import com.android.tools.r8.keepanno.annotations.UsedByNative;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
diff --git a/src/test/java/com/android/tools/r8/keepanno/KeepUsedByReflectionAnnotationTest.java b/src/test/java/com/android/tools/r8/keepanno/KeepUsedByReflectionAnnotationTest.java
index 9e7f5e0..9a1bd85 100644
--- a/src/test/java/com/android/tools/r8/keepanno/KeepUsedByReflectionAnnotationTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/KeepUsedByReflectionAnnotationTest.java
@@ -11,8 +11,8 @@
 import com.android.tools.r8.keepanno.annotations.KeepConstraint;
 import com.android.tools.r8.keepanno.annotations.KeepItemKind;
 import com.android.tools.r8.keepanno.annotations.UsedByReflection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/keepanno/KeepUsesReflectionAnnotationTest.java b/src/test/java/com/android/tools/r8/keepanno/KeepUsesReflectionAnnotationTest.java
index b51c86b..5478d1f 100644
--- a/src/test/java/com/android/tools/r8/keepanno/KeepUsesReflectionAnnotationTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/KeepUsesReflectionAnnotationTest.java
@@ -11,8 +11,8 @@
 
 import com.android.tools.r8.keepanno.annotations.KeepTarget;
 import com.android.tools.r8.keepanno.annotations.UsesReflection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/keepanno/KeepUsesReflectionAnnotationWithAdditionalPreconditionTest.java b/src/test/java/com/android/tools/r8/keepanno/KeepUsesReflectionAnnotationWithAdditionalPreconditionTest.java
index 26e0321..337f785 100644
--- a/src/test/java/com/android/tools/r8/keepanno/KeepUsesReflectionAnnotationWithAdditionalPreconditionTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/KeepUsesReflectionAnnotationWithAdditionalPreconditionTest.java
@@ -9,8 +9,8 @@
 import com.android.tools.r8.keepanno.annotations.KeepCondition;
 import com.android.tools.r8.keepanno.annotations.KeepTarget;
 import com.android.tools.r8.keepanno.annotations.UsesReflection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/keepanno/KeepUsesReflectionAnnotationWithAdditionalPreconditionUnsatisfiedTest.java b/src/test/java/com/android/tools/r8/keepanno/KeepUsesReflectionAnnotationWithAdditionalPreconditionUnsatisfiedTest.java
index 8ac574c..22fb9c6 100644
--- a/src/test/java/com/android/tools/r8/keepanno/KeepUsesReflectionAnnotationWithAdditionalPreconditionUnsatisfiedTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/KeepUsesReflectionAnnotationWithAdditionalPreconditionUnsatisfiedTest.java
@@ -11,8 +11,8 @@
 import com.android.tools.r8.keepanno.annotations.KeepCondition;
 import com.android.tools.r8.keepanno.annotations.KeepTarget;
 import com.android.tools.r8.keepanno.annotations.UsesReflection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/keepanno/KeepUsesReflectionFieldAnnotationTest.java b/src/test/java/com/android/tools/r8/keepanno/KeepUsesReflectionFieldAnnotationTest.java
index e411906..854f00d 100644
--- a/src/test/java/com/android/tools/r8/keepanno/KeepUsesReflectionFieldAnnotationTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/KeepUsesReflectionFieldAnnotationTest.java
@@ -9,8 +9,8 @@
 
 import com.android.tools.r8.keepanno.annotations.KeepTarget;
 import com.android.tools.r8.keepanno.annotations.UsesReflection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/keepanno/KeepUsesReflectionOnFieldTest.java b/src/test/java/com/android/tools/r8/keepanno/KeepUsesReflectionOnFieldTest.java
index 556dd44..1b396ce 100644
--- a/src/test/java/com/android/tools/r8/keepanno/KeepUsesReflectionOnFieldTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/KeepUsesReflectionOnFieldTest.java
@@ -10,8 +10,8 @@
 import com.android.tools.r8.keepanno.annotations.KeepConstraint;
 import com.android.tools.r8.keepanno.annotations.KeepTarget;
 import com.android.tools.r8.keepanno.annotations.UsesReflection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.lang.reflect.Field;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/keepanno/MembersAnnotatedByPatternsTest.java b/src/test/java/com/android/tools/r8/keepanno/MembersAnnotatedByPatternsTest.java
index 8697fa0..c05c0c5 100644
--- a/src/test/java/com/android/tools/r8/keepanno/MembersAnnotatedByPatternsTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/MembersAnnotatedByPatternsTest.java
@@ -14,9 +14,9 @@
 import com.android.tools.r8.keepanno.annotations.KeepTarget;
 import com.android.tools.r8.keepanno.annotations.UsedByReflection;
 import com.android.tools.r8.keepanno.annotations.UsesReflection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
diff --git a/src/test/java/com/android/tools/r8/keepanno/MethodNameStringPatternsTest.java b/src/test/java/com/android/tools/r8/keepanno/MethodNameStringPatternsTest.java
index 836876d..b12cd15 100644
--- a/src/test/java/com/android/tools/r8/keepanno/MethodNameStringPatternsTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/MethodNameStringPatternsTest.java
@@ -13,8 +13,8 @@
 import com.android.tools.r8.keepanno.annotations.StringPattern;
 import com.android.tools.r8.keepanno.annotations.UsedByReflection;
 import com.android.tools.r8.keepanno.annotations.UsesReflection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.lang.reflect.Method;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/keepanno/MethodPatternsTest.java b/src/test/java/com/android/tools/r8/keepanno/MethodPatternsTest.java
index d364ee9..adaa7e6 100644
--- a/src/test/java/com/android/tools/r8/keepanno/MethodPatternsTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/MethodPatternsTest.java
@@ -13,8 +13,8 @@
 import com.android.tools.r8.keepanno.annotations.TypePattern;
 import com.android.tools.r8.keepanno.annotations.UsedByReflection;
 import com.android.tools.r8.keepanno.annotations.UsesReflection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.lang.reflect.Method;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/keepanno/UsedByReflectionMemberInlingingAllowed.java b/src/test/java/com/android/tools/r8/keepanno/UsedByReflectionMemberInlingingAllowed.java
index 649f37e..5d2eb13 100644
--- a/src/test/java/com/android/tools/r8/keepanno/UsedByReflectionMemberInlingingAllowed.java
+++ b/src/test/java/com/android/tools/r8/keepanno/UsedByReflectionMemberInlingingAllowed.java
@@ -11,10 +11,10 @@
 
 import com.android.tools.r8.keepanno.annotations.KeepItemKind;
 import com.android.tools.r8.keepanno.annotations.UsedByReflection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/keepanno/UsedByReflectionWithNonMatchingMemberPatternsTest.java b/src/test/java/com/android/tools/r8/keepanno/UsedByReflectionWithNonMatchingMemberPatternsTest.java
index 1f6659a..93d514e 100644
--- a/src/test/java/com/android/tools/r8/keepanno/UsedByReflectionWithNonMatchingMemberPatternsTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/UsedByReflectionWithNonMatchingMemberPatternsTest.java
@@ -5,7 +5,7 @@
 
 import com.android.tools.r8.keepanno.annotations.KeepItemKind;
 import com.android.tools.r8.keepanno.annotations.UsedByReflection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/keepanno/androidx/AnnotationPatternAnyRetentionTest.java b/src/test/java/com/android/tools/r8/keepanno/androidx/AnnotationPatternAnyRetentionTest.java
index 1f60688..03c2c45 100644
--- a/src/test/java/com/android/tools/r8/keepanno/androidx/AnnotationPatternAnyRetentionTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/androidx/AnnotationPatternAnyRetentionTest.java
@@ -16,9 +16,9 @@
 import com.android.tools.r8.KotlinCompilerTool.KotlinCompilerVersion;
 import com.android.tools.r8.keepanno.KeepAnnoParameters;
 import com.android.tools.r8.keepanno.KeepAnnoTestBase;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
diff --git a/src/test/java/com/android/tools/r8/keepanno/androidx/AnnotationPatternClassRetentionTest.java b/src/test/java/com/android/tools/r8/keepanno/androidx/AnnotationPatternClassRetentionTest.java
index 8ce1296..7025ddd 100644
--- a/src/test/java/com/android/tools/r8/keepanno/androidx/AnnotationPatternClassRetentionTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/androidx/AnnotationPatternClassRetentionTest.java
@@ -17,9 +17,9 @@
 import com.android.tools.r8.KotlinCompilerTool.KotlinCompilerVersion;
 import com.android.tools.r8.keepanno.KeepAnnoParameters;
 import com.android.tools.r8.keepanno.KeepAnnoTestBase;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
diff --git a/src/test/java/com/android/tools/r8/keepanno/androidx/KeepAnnoTestExtractedRulesBase.java b/src/test/java/com/android/tools/r8/keepanno/androidx/KeepAnnoTestExtractedRulesBase.java
index 15631d9..ac1e6c9 100644
--- a/src/test/java/com/android/tools/r8/keepanno/androidx/KeepAnnoTestExtractedRulesBase.java
+++ b/src/test/java/com/android/tools/r8/keepanno/androidx/KeepAnnoTestExtractedRulesBase.java
@@ -3,7 +3,7 @@
 // BSD-style license that can be found in the LICENSE file.
 package com.android.tools.r8.keepanno.androidx;
 
-import static com.android.tools.r8.utils.FileUtils.isClassFile;
+import static com.android.tools.r8.utils.internal.FileUtils.isClassFile;
 import static org.junit.Assume.assumeFalse;
 
 import com.android.tools.r8.DataEntryResource;
@@ -27,9 +27,9 @@
 import com.android.tools.r8.transformers.ClassFileTransformer.FieldPredicate;
 import com.android.tools.r8.transformers.ClassFileTransformer.MethodPredicate;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.internal.ThrowingConsumer;
 import com.android.tools.r8.utils.ZipUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.ThrowingConsumer;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Iterables;
 import com.google.common.io.ByteStreams;
diff --git a/src/test/java/com/android/tools/r8/keepanno/androidx/KeepUnconditionallyKeepTest.java b/src/test/java/com/android/tools/r8/keepanno/androidx/KeepUnconditionallyKeepTest.java
index 791c649..03cfcd1 100644
--- a/src/test/java/com/android/tools/r8/keepanno/androidx/KeepUnconditionallyKeepTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/androidx/KeepUnconditionallyKeepTest.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.transformers.ClassFileTransformer.AnnotationBuilder;
 import com.android.tools.r8.transformers.ClassFileTransformer.FieldPredicate;
 import com.android.tools.r8.transformers.ClassFileTransformer.MethodPredicate;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/keepanno/androidx/KeepUsesReflectionForInstantiationAnyArgsConstructorTest.java b/src/test/java/com/android/tools/r8/keepanno/androidx/KeepUsesReflectionForInstantiationAnyArgsConstructorTest.java
index 8f69c30..93afe5a 100644
--- a/src/test/java/com/android/tools/r8/keepanno/androidx/KeepUsesReflectionForInstantiationAnyArgsConstructorTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/androidx/KeepUsesReflectionForInstantiationAnyArgsConstructorTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.transformers.ClassFileTransformer.AnnotationContentBuilder;
 import com.android.tools.r8.transformers.ClassFileTransformer.MethodPredicate;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/keepanno/androidx/KeepUsesReflectionForInstantiationMultipleConstructorsTest.java b/src/test/java/com/android/tools/r8/keepanno/androidx/KeepUsesReflectionForInstantiationMultipleConstructorsTest.java
index fa4161a..81c9017 100644
--- a/src/test/java/com/android/tools/r8/keepanno/androidx/KeepUsesReflectionForInstantiationMultipleConstructorsTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/androidx/KeepUsesReflectionForInstantiationMultipleConstructorsTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.ToolHelper.DexVm.Version;
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.transformers.ClassFileTransformer.MethodPredicate;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/keepanno/androidx/KeepUsesReflectionForInstantiationNoArgsConstructorTest.java b/src/test/java/com/android/tools/r8/keepanno/androidx/KeepUsesReflectionForInstantiationNoArgsConstructorTest.java
index 51e1b7b..5f7f3df 100644
--- a/src/test/java/com/android/tools/r8/keepanno/androidx/KeepUsesReflectionForInstantiationNoArgsConstructorTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/androidx/KeepUsesReflectionForInstantiationNoArgsConstructorTest.java
@@ -15,7 +15,7 @@
 import com.android.tools.r8.transformers.ClassFileTransformer.AnnotationContentBuilder;
 import com.android.tools.r8.transformers.ClassFileTransformer.MethodPredicate;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/keepanno/androidx/KeepUsesReflectionToAccessFieldTest.java b/src/test/java/com/android/tools/r8/keepanno/androidx/KeepUsesReflectionToAccessFieldTest.java
index 1ec7d9b..23169e8 100644
--- a/src/test/java/com/android/tools/r8/keepanno/androidx/KeepUsesReflectionToAccessFieldTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/androidx/KeepUsesReflectionToAccessFieldTest.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.transformers.ClassFileTransformer.AnnotationContentBuilder;
 import com.android.tools.r8.transformers.ClassFileTransformer.MethodPredicate;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/keepanno/androidx/KeepUsesReflectionToAccessMethodTest.java b/src/test/java/com/android/tools/r8/keepanno/androidx/KeepUsesReflectionToAccessMethodTest.java
index e002dd4..271aa2a 100644
--- a/src/test/java/com/android/tools/r8/keepanno/androidx/KeepUsesReflectionToAccessMethodTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/androidx/KeepUsesReflectionToAccessMethodTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.transformers.ClassFileTransformer.AnnotationContentBuilder;
 import com.android.tools.r8.transformers.ClassFileTransformer.MethodPredicate;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/keepanno/api/genericsignature/KeepGenericSignaturesApiTest.java b/src/test/java/com/android/tools/r8/keepanno/api/genericsignature/KeepGenericSignaturesApiTest.java
index 9560728..ceed5bf 100644
--- a/src/test/java/com/android/tools/r8/keepanno/api/genericsignature/KeepGenericSignaturesApiTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/api/genericsignature/KeepGenericSignaturesApiTest.java
@@ -13,9 +13,9 @@
 import com.android.tools.r8.keepanno.KeepAnnoParameters;
 import com.android.tools.r8.keepanno.KeepAnnoTestBase;
 import com.android.tools.r8.keepanno.KeepAnnoTestUtils;
-import com.android.tools.r8.utils.internal.Box;
 import com.android.tools.r8.utils.ListUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.Box;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Path;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/keepanno/ast/KeepEdgeAstTest.java b/src/test/java/com/android/tools/r8/keepanno/ast/KeepEdgeAstTest.java
index 3c46771..efae92f 100644
--- a/src/test/java/com/android/tools/r8/keepanno/ast/KeepEdgeAstTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/ast/KeepEdgeAstTest.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.keepanno.ast.KeepBindings.KeepBindingSymbol;
 import com.android.tools.r8.keepanno.keeprules.KeepRuleExtractor;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/keepanno/classpatterns/ClassNamePatternsTest.java b/src/test/java/com/android/tools/r8/keepanno/classpatterns/ClassNamePatternsTest.java
index c64f958..1682e45 100644
--- a/src/test/java/com/android/tools/r8/keepanno/classpatterns/ClassNamePatternsTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/classpatterns/ClassNamePatternsTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.keepanno.annotations.TypePattern;
 import com.android.tools.r8.keepanno.annotations.UsedByReflection;
 import com.android.tools.r8.keepanno.annotations.UsesReflection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.lang.reflect.InvocationTargetException;
 import java.util.Arrays;
diff --git a/src/test/java/com/android/tools/r8/keepanno/compatissues/BackReferenceIssuesTest.java b/src/test/java/com/android/tools/r8/keepanno/compatissues/BackReferenceIssuesTest.java
index 85464e5..65574ca 100644
--- a/src/test/java/com/android/tools/r8/keepanno/compatissues/BackReferenceIssuesTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/compatissues/BackReferenceIssuesTest.java
@@ -17,7 +17,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestRunResult;
 import com.android.tools.r8.TestShrinkerBuilder;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/keepanno/compatissues/ClassesWithMembersOnFieldsIssuesTest.java b/src/test/java/com/android/tools/r8/keepanno/compatissues/ClassesWithMembersOnFieldsIssuesTest.java
index e41895a..500948c 100644
--- a/src/test/java/com/android/tools/r8/keepanno/compatissues/ClassesWithMembersOnFieldsIssuesTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/compatissues/ClassesWithMembersOnFieldsIssuesTest.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestRunResult;
 import com.android.tools.r8.TestShrinkerBuilder;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/keepanno/compatissues/ClassesWithMembersOnMethodsIssuesTest.java b/src/test/java/com/android/tools/r8/keepanno/compatissues/ClassesWithMembersOnMethodsIssuesTest.java
index fc594c4..41a6644 100644
--- a/src/test/java/com/android/tools/r8/keepanno/compatissues/ClassesWithMembersOnMethodsIssuesTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/compatissues/ClassesWithMembersOnMethodsIssuesTest.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestRunResult;
 import com.android.tools.r8.TestShrinkerBuilder;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/keepanno/compatissues/DefaultInitClassWithMembersRuleTest.java b/src/test/java/com/android/tools/r8/keepanno/compatissues/DefaultInitClassWithMembersRuleTest.java
index 5149049..0fbe6ae 100644
--- a/src/test/java/com/android/tools/r8/keepanno/compatissues/DefaultInitClassWithMembersRuleTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/compatissues/DefaultInitClassWithMembersRuleTest.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.TestRunResult;
 import com.android.tools.r8.TestShrinkerBuilder;
 import com.android.tools.r8.transformers.ClassFileTransformer.FieldPredicate;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/keepanno/compatissues/EmptyClassWithMembersRuleTest.java b/src/test/java/com/android/tools/r8/keepanno/compatissues/EmptyClassWithMembersRuleTest.java
index 1f16eb9..2ba35d3 100644
--- a/src/test/java/com/android/tools/r8/keepanno/compatissues/EmptyClassWithMembersRuleTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/compatissues/EmptyClassWithMembersRuleTest.java
@@ -17,7 +17,7 @@
 import com.android.tools.r8.ThrowableConsumer;
 import com.android.tools.r8.transformers.ClassFileTransformer.FieldPredicate;
 import com.android.tools.r8.transformers.ClassFileTransformer.MethodPredicate;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/keepanno/compatissues/NonDefaultInitClassWithMembersRuleTest.java b/src/test/java/com/android/tools/r8/keepanno/compatissues/NonDefaultInitClassWithMembersRuleTest.java
index 9b46168..df4108b 100644
--- a/src/test/java/com/android/tools/r8/keepanno/compatissues/NonDefaultInitClassWithMembersRuleTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/compatissues/NonDefaultInitClassWithMembersRuleTest.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.TestRunResult;
 import com.android.tools.r8.TestShrinkerBuilder;
 import com.android.tools.r8.transformers.ClassFileTransformer.FieldPredicate;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/keepanno/doctests/ForApiDocumentationTest.java b/src/test/java/com/android/tools/r8/keepanno/doctests/ForApiDocumentationTest.java
index 63a3ca4..fb78026 100644
--- a/src/test/java/com/android/tools/r8/keepanno/doctests/ForApiDocumentationTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/doctests/ForApiDocumentationTest.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.keepanno.annotations.KeepForApi;
 import com.android.tools.r8.keepanno.annotations.MemberAccessFlags;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.lang.reflect.Method;
 import java.util.ArrayList;
diff --git a/src/test/java/com/android/tools/r8/keepanno/doctests/MainMethodsDocumentationTest.java b/src/test/java/com/android/tools/r8/keepanno/doctests/MainMethodsDocumentationTest.java
index de40ed9..8eadcd6 100644
--- a/src/test/java/com/android/tools/r8/keepanno/doctests/MainMethodsDocumentationTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/doctests/MainMethodsDocumentationTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.keepanno.annotations.KeepItemKind;
 import com.android.tools.r8.keepanno.annotations.KeepTarget;
 import com.android.tools.r8.keepanno.annotations.MethodAccessFlags;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/keepanno/doctests/SignatureConstraintsDocumentationTest.java b/src/test/java/com/android/tools/r8/keepanno/doctests/SignatureConstraintsDocumentationTest.java
index 2473300..bcd38cd 100644
--- a/src/test/java/com/android/tools/r8/keepanno/doctests/SignatureConstraintsDocumentationTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/doctests/SignatureConstraintsDocumentationTest.java
@@ -6,7 +6,7 @@
 import com.android.tools.r8.keepanno.KeepAnnoParameters;
 import com.android.tools.r8.keepanno.KeepAnnoTestBase;
 import com.android.tools.r8.keepanno.doctests.GenericSignaturePrinter.TestClass;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/keepanno/doctests/UsesReflectionAnnotationsDocumentationTest.java b/src/test/java/com/android/tools/r8/keepanno/doctests/UsesReflectionAnnotationsDocumentationTest.java
index 5d5cca9..98da254 100644
--- a/src/test/java/com/android/tools/r8/keepanno/doctests/UsesReflectionAnnotationsDocumentationTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/doctests/UsesReflectionAnnotationsDocumentationTest.java
@@ -15,8 +15,8 @@
 import com.android.tools.r8.keepanno.annotations.KeepTarget;
 import com.android.tools.r8.keepanno.annotations.UsesReflection;
 import com.android.tools.r8.keepanno.doctests.UsesReflectionAnnotationsDocumentationTest.Example1.MyAnnotationPrinter.MyClass;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
diff --git a/src/test/java/com/android/tools/r8/keepanno/doctests/UsesReflectionDocumentationTest.java b/src/test/java/com/android/tools/r8/keepanno/doctests/UsesReflectionDocumentationTest.java
index 4cc673c..65fc283 100644
--- a/src/test/java/com/android/tools/r8/keepanno/doctests/UsesReflectionDocumentationTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/doctests/UsesReflectionDocumentationTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.keepanno.annotations.KeepTarget;
 import com.android.tools.r8.keepanno.annotations.UsedByReflection;
 import com.android.tools.r8.keepanno.annotations.UsesReflection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.lang.reflect.Field;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/keepanno/utils/KeepAnnoMarkdownGenerator.java b/src/test/java/com/android/tools/r8/keepanno/utils/KeepAnnoMarkdownGenerator.java
index d19d5c9..f67bf63 100644
--- a/src/test/java/com/android/tools/r8/keepanno/utils/KeepAnnoMarkdownGenerator.java
+++ b/src/test/java/com/android/tools/r8/keepanno/utils/KeepAnnoMarkdownGenerator.java
@@ -18,8 +18,8 @@
 import com.android.tools.r8.keepanno.utils.KeepItemAnnotationGenerator.Group;
 import com.android.tools.r8.keepanno.utils.KeepItemAnnotationGenerator.GroupMember;
 import com.android.tools.r8.references.ClassReference;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableMap;
 import java.io.IOException;
 import java.nio.charset.StandardCharsets;
diff --git a/src/test/java/com/android/tools/r8/keepanno/utils/KeepItemAnnotationGenerator.java b/src/test/java/com/android/tools/r8/keepanno/utils/KeepItemAnnotationGenerator.java
index cd02cc5..3e72e8b 100644
--- a/src/test/java/com/android/tools/r8/keepanno/utils/KeepItemAnnotationGenerator.java
+++ b/src/test/java/com/android/tools/r8/keepanno/utils/KeepItemAnnotationGenerator.java
@@ -15,9 +15,9 @@
 import com.android.tools.r8.references.ClassReference;
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.StringUtils;
-import com.android.tools.r8.utils.StringUtils.BraceType;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils.BraceType;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import com.google.common.base.Strings;
 import com.google.common.collect.ImmutableList;
diff --git a/src/test/java/com/android/tools/r8/keepanno/utils/KeepItemGeneratedFilesTest.java b/src/test/java/com/android/tools/r8/keepanno/utils/KeepItemGeneratedFilesTest.java
index d8afd84..c9d095c 100644
--- a/src/test/java/com/android/tools/r8/keepanno/utils/KeepItemGeneratedFilesTest.java
+++ b/src/test/java/com/android/tools/r8/keepanno/utils/KeepItemGeneratedFilesTest.java
@@ -8,7 +8,7 @@
 
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.keepanno.utils.KeepItemAnnotationGenerator.Generator;
-import com.android.tools.r8.utils.FileUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import java.io.IOException;
 import java.nio.charset.StandardCharsets;
 import org.junit.Assume;
diff --git a/src/test/java/com/android/tools/r8/kotlin/AbstractR8KotlinTestBase.java b/src/test/java/com/android/tools/r8/kotlin/AbstractR8KotlinTestBase.java
index 1660e75..46c8af7 100644
--- a/src/test/java/com/android/tools/r8/kotlin/AbstractR8KotlinTestBase.java
+++ b/src/test/java/com/android/tools/r8/kotlin/AbstractR8KotlinTestBase.java
@@ -26,12 +26,12 @@
 import com.android.tools.r8.jasmin.JasminBuilder.ClassBuilder;
 import com.android.tools.r8.naming.MemberNaming.MethodSignature;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FieldSubject;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.ArrayList;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/kotlin/KotlinDuplicateAnnotationTest.java b/src/test/java/com/android/tools/r8/kotlin/KotlinDuplicateAnnotationTest.java
index 168e858..44881b9 100644
--- a/src/test/java/com/android/tools/r8/kotlin/KotlinDuplicateAnnotationTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/KotlinDuplicateAnnotationTest.java
@@ -13,9 +13,9 @@
 import com.android.tools.r8.KotlinCompilerTool.KotlinCompilerVersion;
 import com.android.tools.r8.KotlinTestParameters;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.internal.BooleanUtils;
 import com.android.tools.r8.utils.InternalOptions;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.util.Collection;
diff --git a/src/test/java/com/android/tools/r8/kotlin/KotlinIntrinsicsInlineTest.java b/src/test/java/com/android/tools/r8/kotlin/KotlinIntrinsicsInlineTest.java
index 86219dd..363956b 100644
--- a/src/test/java/com/android/tools/r8/kotlin/KotlinIntrinsicsInlineTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/KotlinIntrinsicsInlineTest.java
@@ -14,10 +14,10 @@
 import com.android.tools.r8.KotlinTestParameters;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Collection;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/kotlin/KotlinSourceDebugExtensionParserTest.java b/src/test/java/com/android/tools/r8/kotlin/KotlinSourceDebugExtensionParserTest.java
index 1b91f8b..4aff93a 100644
--- a/src/test/java/com/android/tools/r8/kotlin/KotlinSourceDebugExtensionParserTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/KotlinSourceDebugExtensionParserTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.kotlin.KotlinSourceDebugExtensionParser.KotlinSourceDebugExtensionParserResult;
 import com.android.tools.r8.kotlin.KotlinSourceDebugExtensionParser.Position;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/kotlin/ProcessKotlinNullChecksTest.java b/src/test/java/com/android/tools/r8/kotlin/ProcessKotlinNullChecksTest.java
index 505f0a1..673179b 100644
--- a/src/test/java/com/android/tools/r8/kotlin/ProcessKotlinNullChecksTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/ProcessKotlinNullChecksTest.java
@@ -9,9 +9,9 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableMap;
 import java.io.IOException;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/kotlin/SimplifyIfNotNullKotlinTest.java b/src/test/java/com/android/tools/r8/kotlin/SimplifyIfNotNullKotlinTest.java
index b1a4cfe..41c2f36 100644
--- a/src/test/java/com/android/tools/r8/kotlin/SimplifyIfNotNullKotlinTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/SimplifyIfNotNullKotlinTest.java
@@ -8,10 +8,10 @@
 import com.android.tools.r8.KotlinTestParameters;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.naming.MemberNaming.MethodSignature;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.Collection;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/kotlin/access/B369418242Test.java b/src/test/java/com/android/tools/r8/kotlin/access/B369418242Test.java
index c5f3e00..bda662a 100644
--- a/src/test/java/com/android/tools/r8/kotlin/access/B369418242Test.java
+++ b/src/test/java/com/android/tools/r8/kotlin/access/B369418242Test.java
@@ -13,8 +13,8 @@
 import com.android.tools.r8.kotlin.access.b369418242.pkg.B;
 import com.android.tools.r8.kotlin.access.b369418242.pkg.Helper;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.ZipUtils.ZipBuilder;
+import com.android.tools.r8.utils.internal.FileUtils;
 import java.nio.file.Path;
 import java.nio.file.Paths;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/kotlin/inline/KotlinInlineClassLevelLibraryTest.java b/src/test/java/com/android/tools/r8/kotlin/inline/KotlinInlineClassLevelLibraryTest.java
index b253a2b..9bfab81 100644
--- a/src/test/java/com/android/tools/r8/kotlin/inline/KotlinInlineClassLevelLibraryTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/inline/KotlinInlineClassLevelLibraryTest.java
@@ -10,10 +10,10 @@
 import com.android.tools.r8.KotlinTestParameters;
 import com.android.tools.r8.R8FullTestBuilder;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassOrMemberSubject;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/kotlin/inline/KotlinInlineCompanionLibraryTest.java b/src/test/java/com/android/tools/r8/kotlin/inline/KotlinInlineCompanionLibraryTest.java
index c93b22b..df0090a 100644
--- a/src/test/java/com/android/tools/r8/kotlin/inline/KotlinInlineCompanionLibraryTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/inline/KotlinInlineCompanionLibraryTest.java
@@ -10,10 +10,10 @@
 import com.android.tools.r8.KotlinTestParameters;
 import com.android.tools.r8.R8FullTestBuilder;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassOrMemberSubject;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/kotlin/inline/KotlinInlineCompanionOptionalParamsLibraryTest.java b/src/test/java/com/android/tools/r8/kotlin/inline/KotlinInlineCompanionOptionalParamsLibraryTest.java
index a6d7ff4..7b378d8 100644
--- a/src/test/java/com/android/tools/r8/kotlin/inline/KotlinInlineCompanionOptionalParamsLibraryTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/inline/KotlinInlineCompanionOptionalParamsLibraryTest.java
@@ -10,10 +10,10 @@
 import com.android.tools.r8.KotlinTestParameters;
 import com.android.tools.r8.R8FullTestBuilder;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassOrMemberSubject;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/kotlin/inline/KotlinInlineFileLevelLibraryTest.java b/src/test/java/com/android/tools/r8/kotlin/inline/KotlinInlineFileLevelLibraryTest.java
index 411f962..0ea1394 100644
--- a/src/test/java/com/android/tools/r8/kotlin/inline/KotlinInlineFileLevelLibraryTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/inline/KotlinInlineFileLevelLibraryTest.java
@@ -10,10 +10,10 @@
 import com.android.tools.r8.KotlinTestParameters;
 import com.android.tools.r8.R8FullTestBuilder;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassOrMemberSubject;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/kotlin/lambda/KotlinLambdaMergingCapturesKotlinStyleTest.java b/src/test/java/com/android/tools/r8/kotlin/lambda/KotlinLambdaMergingCapturesKotlinStyleTest.java
index 18dc4ef..bdde715 100644
--- a/src/test/java/com/android/tools/r8/kotlin/lambda/KotlinLambdaMergingCapturesKotlinStyleTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/lambda/KotlinLambdaMergingCapturesKotlinStyleTest.java
@@ -17,9 +17,9 @@
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Path;
 import java.util.ArrayList;
diff --git a/src/test/java/com/android/tools/r8/kotlin/lambda/KotlinLambdaMergingKeepAttributesKotlinStyleTest.java b/src/test/java/com/android/tools/r8/kotlin/lambda/KotlinLambdaMergingKeepAttributesKotlinStyleTest.java
index 366e992..ec8b71b 100644
--- a/src/test/java/com/android/tools/r8/kotlin/lambda/KotlinLambdaMergingKeepAttributesKotlinStyleTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/lambda/KotlinLambdaMergingKeepAttributesKotlinStyleTest.java
@@ -18,10 +18,10 @@
 import com.android.tools.r8.references.ClassReference;
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.HorizontallyMergedClassesInspector;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Path;
 import java.util.ArrayList;
diff --git a/src/test/java/com/android/tools/r8/kotlin/lambda/KotlinLambdaMergingSingletonTest.java b/src/test/java/com/android/tools/r8/kotlin/lambda/KotlinLambdaMergingSingletonTest.java
index 8a5c5b6..4c5efa3 100644
--- a/src/test/java/com/android/tools/r8/kotlin/lambda/KotlinLambdaMergingSingletonTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/lambda/KotlinLambdaMergingSingletonTest.java
@@ -13,10 +13,10 @@
 import com.android.tools.r8.KotlinTestParameters;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.references.ClassReference;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.HorizontallyMergedClassesInspector;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Path;
 import java.util.ArrayList;
diff --git a/src/test/java/com/android/tools/r8/kotlin/lambda/KotlinLambdaMergingTrivialJavaStyleTest.java b/src/test/java/com/android/tools/r8/kotlin/lambda/KotlinLambdaMergingTrivialJavaStyleTest.java
index a9e5541..1c1a473 100644
--- a/src/test/java/com/android/tools/r8/kotlin/lambda/KotlinLambdaMergingTrivialJavaStyleTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/lambda/KotlinLambdaMergingTrivialJavaStyleTest.java
@@ -20,10 +20,10 @@
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.HorizontallyMergedClassesInspector;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/kotlin/lambda/KotlinLambdaMergingTrivialKotlinStyleTest.java b/src/test/java/com/android/tools/r8/kotlin/lambda/KotlinLambdaMergingTrivialKotlinStyleTest.java
index 2ea6a78..fde4084 100644
--- a/src/test/java/com/android/tools/r8/kotlin/lambda/KotlinLambdaMergingTrivialKotlinStyleTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/lambda/KotlinLambdaMergingTrivialKotlinStyleTest.java
@@ -16,10 +16,10 @@
 import com.android.tools.r8.references.ClassReference;
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.HorizontallyMergedClassesInspector;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Path;
 import java.util.ArrayList;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataFirstToLatestTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataFirstToLatestTest.java
index a83e200..4ae5573 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataFirstToLatestTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataFirstToLatestTest.java
@@ -15,7 +15,7 @@
 import com.android.tools.r8.KotlinTestParameters;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.Collection;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteAllowAccessModificationTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteAllowAccessModificationTest.java
index ac0bb74..ad0467d 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteAllowAccessModificationTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteAllowAccessModificationTest.java
@@ -15,10 +15,10 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.ToolHelper.ProcessResult;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.Collection;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteAnnotationTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteAnnotationTest.java
index 9d6ae05..22b1090 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteAnnotationTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteAnnotationTest.java
@@ -17,10 +17,10 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.KmTypeAliasSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.Collection;
 import java.util.Map;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteBoxedTypesTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteBoxedTypesTest.java
index c18cf84..5837c13 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteBoxedTypesTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteBoxedTypesTest.java
@@ -8,8 +8,8 @@
 import com.android.tools.r8.KotlinTestParameters;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.Collection;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteContextParametersTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteContextParametersTest.java
index b0f5dc1..265658f 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteContextParametersTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteContextParametersTest.java
@@ -15,10 +15,10 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteContextReceiverTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteContextReceiverTest.java
index 0669dec..9d9b278 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteContextReceiverTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteContextReceiverTest.java
@@ -18,10 +18,10 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteCrossinlineAnonFunctionTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteCrossinlineAnonFunctionTest.java
index ab2426d..e978f87 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteCrossinlineAnonFunctionTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteCrossinlineAnonFunctionTest.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.KotlinTestParameters;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.Collection;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteCrossinlineBlockTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteCrossinlineBlockTest.java
index 903c9a7..c374452 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteCrossinlineBlockTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteCrossinlineBlockTest.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.KotlinTestParameters;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.Collection;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteCrossinlineConcreteFunctionTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteCrossinlineConcreteFunctionTest.java
index ce207bf..e2e058d 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteCrossinlineConcreteFunctionTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteCrossinlineConcreteFunctionTest.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.KotlinTestParameters;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.Collection;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteDelegatedPropertyTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteDelegatedPropertyTest.java
index dc15445..1e96f35 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteDelegatedPropertyTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteDelegatedPropertyTest.java
@@ -18,9 +18,9 @@
 import com.android.tools.r8.kotlin.KotlinMetadataWriter;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.Collection;
 import kotlin.metadata.jvm.KotlinClassMetadata;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteDependentKeepTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteDependentKeepTest.java
index 65513b4..b6f82b5 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteDependentKeepTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteDependentKeepTest.java
@@ -10,9 +10,9 @@
 import com.android.tools.r8.CompilationFailedException;
 import com.android.tools.r8.KotlinTestParameters;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FoundClassSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.util.Collection;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteFlexibleUpperBoundTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteFlexibleUpperBoundTest.java
index 85362f8..8e05b5a 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteFlexibleUpperBoundTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteFlexibleUpperBoundTest.java
@@ -17,12 +17,12 @@
 import com.android.tools.r8.KotlinTestParameters;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.KmPropertySubject;
 import com.android.tools.r8.utils.codeinspector.KmTypeProjectionSubject;
 import com.android.tools.r8.utils.codeinspector.KmTypeSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.Collection;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInClasspathTypeTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInClasspathTypeTest.java
index 8d87af0..69b2d3a 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInClasspathTypeTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInClasspathTypeTest.java
@@ -16,12 +16,12 @@
 import com.android.tools.r8.KotlinTestParameters;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.KmClassSubject;
 import com.android.tools.r8.utils.codeinspector.KmFunctionSubject;
 import com.android.tools.r8.utils.codeinspector.KmPackageSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.Collection;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInCompanionTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInCompanionTest.java
index f2ed57a..699fdf7 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInCompanionTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInCompanionTest.java
@@ -17,13 +17,13 @@
 import com.android.tools.r8.KotlinTestParameters;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FieldSubject;
 import com.android.tools.r8.utils.codeinspector.KmClassSubject;
 import com.android.tools.r8.utils.codeinspector.KmPropertySubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.Collection;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInExtensionFunctionTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInExtensionFunctionTest.java
index 5cd719d..bc53f47 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInExtensionFunctionTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInExtensionFunctionTest.java
@@ -20,8 +20,6 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.ZipUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
@@ -33,6 +31,8 @@
 import com.android.tools.r8.utils.codeinspector.KmValueParameterSubject;
 import com.android.tools.r8.utils.codeinspector.Matchers;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInExtensionPropertyTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInExtensionPropertyTest.java
index 11afb11..2dca30f 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInExtensionPropertyTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInExtensionPropertyTest.java
@@ -19,7 +19,6 @@
 import com.android.tools.r8.KotlinTestParameters;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.KmClassSubject;
@@ -27,6 +26,7 @@
 import com.android.tools.r8.utils.codeinspector.KmPackageSubject;
 import com.android.tools.r8.utils.codeinspector.KmPropertySubject;
 import com.android.tools.r8.utils.codeinspector.Matchers;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.Collection;
 import java.util.List;
@@ -219,4 +219,4 @@
     assertThat(kmProperty, isExtensionProperty());
     assertNotNull(kmProperty.getterSignature());
   }
-}
\ No newline at end of file
+}
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInFunctionTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInFunctionTest.java
index 78a4b15..aa6dc53 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInFunctionTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInFunctionTest.java
@@ -18,7 +18,6 @@
 import com.android.tools.r8.KotlinTestParameters;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.KmClassSubject;
@@ -26,6 +25,7 @@
 import com.android.tools.r8.utils.codeinspector.KmPackageSubject;
 import com.android.tools.r8.utils.codeinspector.Matchers;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.Collection;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInFunctionWithDefaultValueTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInFunctionWithDefaultValueTest.java
index fe8617a..74dd5ce 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInFunctionWithDefaultValueTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInFunctionWithDefaultValueTest.java
@@ -16,7 +16,6 @@
 import com.android.tools.r8.KotlinTestParameters;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.KmFunctionSubject;
@@ -25,6 +24,7 @@
 import com.android.tools.r8.utils.codeinspector.KmTypeSubject;
 import com.android.tools.r8.utils.codeinspector.KmValueParameterSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.Collection;
 import java.util.List;
@@ -140,4 +140,4 @@
     assertTrue(valueParameter.declaresDefaultValue());
     assertEquals(KT_STRING, valueParameter.type().descriptor());
   }
-}
\ No newline at end of file
+}
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInFunctionWithVarargTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInFunctionWithVarargTest.java
index ca055ae..546c259 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInFunctionWithVarargTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInFunctionWithVarargTest.java
@@ -18,7 +18,6 @@
 import com.android.tools.r8.KotlinTestParameters;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.KmFunctionSubject;
@@ -27,6 +26,7 @@
 import com.android.tools.r8.utils.codeinspector.KmTypeSubject;
 import com.android.tools.r8.utils.codeinspector.KmValueParameterSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.Collection;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInLibraryTypeTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInLibraryTypeTest.java
index 36ac05d..6650ce1 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInLibraryTypeTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInLibraryTypeTest.java
@@ -12,10 +12,10 @@
 import com.android.tools.r8.KotlinTestParameters;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.KmPackageSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.Collection;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInMultifileClassTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInMultifileClassTest.java
index 627fccd..4c4ab6e 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInMultifileClassTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInMultifileClassTest.java
@@ -21,13 +21,13 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.ToolHelper.ProcessResult;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.AnnotationSubject;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.KmFunctionSubject;
 import com.android.tools.r8.utils.codeinspector.KmPackageSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.Collection;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInNamedArgumentsTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInNamedArgumentsTest.java
index b02a484..d4962d4 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInNamedArgumentsTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInNamedArgumentsTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestShrinkerBuilder;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.Collection;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInNestedClassTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInNestedClassTest.java
index a65c88f..0a962d0 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInNestedClassTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInNestedClassTest.java
@@ -17,10 +17,10 @@
 import com.android.tools.r8.KotlinTestParameters;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.KmClassSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.Collection;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInParameterTypeTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInParameterTypeTest.java
index ceba2ee..d84c0ad 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInParameterTypeTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInParameterTypeTest.java
@@ -15,10 +15,10 @@
 import com.android.tools.r8.KotlinTestParameters;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.KmClassSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.Collection;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInPropertyTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInPropertyTest.java
index 50fd24a..ead47ff 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInPropertyTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInPropertyTest.java
@@ -21,13 +21,13 @@
 import com.android.tools.r8.KotlinTestParameters;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FieldSubject;
 import com.android.tools.r8.utils.codeinspector.KmClassSubject;
 import com.android.tools.r8.utils.codeinspector.KmPropertySubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.Collection;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInPropertyTypeTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInPropertyTypeTest.java
index 1afb9ac..52aa203 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInPropertyTypeTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInPropertyTypeTest.java
@@ -15,10 +15,10 @@
 import com.android.tools.r8.KotlinTestParameters;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.KmClassSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.Collection;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInReturnTypeTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInReturnTypeTest.java
index 6052962..9a51758 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInReturnTypeTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInReturnTypeTest.java
@@ -15,10 +15,10 @@
 import com.android.tools.r8.KotlinTestParameters;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.KmClassSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.Collection;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInSealedClassNestedTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInSealedClassNestedTest.java
index d1e19fd..7db139b 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInSealedClassNestedTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInSealedClassNestedTest.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.Collection;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInSealedClassTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInSealedClassTest.java
index 76a2460..e0f7537 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInSealedClassTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInSealedClassTest.java
@@ -21,12 +21,12 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.ToolHelper.ProcessResult;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.KmClassSubject;
 import com.android.tools.r8.utils.codeinspector.KmFunctionSubject;
 import com.android.tools.r8.utils.codeinspector.KmPackageSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.Collection;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInSuperTypeTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInSuperTypeTest.java
index fc972c7..db98723 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInSuperTypeTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInSuperTypeTest.java
@@ -16,10 +16,10 @@
 import com.android.tools.r8.KotlinTestParameters;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.KmClassSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.Collection;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInTypeAliasTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInTypeAliasTest.java
index d4db9f0..319c658 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInTypeAliasTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInTypeAliasTest.java
@@ -20,7 +20,6 @@
 import com.android.tools.r8.kotlin.Kotlin.ClassClassifiers;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.KmClassifierSubject;
@@ -29,6 +28,7 @@
 import com.android.tools.r8.utils.codeinspector.KmTypeProjectionSubject;
 import com.android.tools.r8.utils.codeinspector.KmTypeSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.Collection;
 import org.junit.Assume;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInTypeArgumentsTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInTypeArgumentsTest.java
index 042e878..46114ff 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInTypeArgumentsTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInTypeArgumentsTest.java
@@ -18,7 +18,6 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.kotlin.KotlinFlagUtils;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.KmClassSubject;
@@ -30,6 +29,7 @@
 import com.android.tools.r8.utils.codeinspector.KmTypeProjectionSubject;
 import com.android.tools.r8.utils.codeinspector.KmTypeSubject;
 import com.android.tools.r8.utils.codeinspector.KmValueParameterSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableMap;
 import java.nio.file.Path;
 import java.util.Collection;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInlineClassIncludeDescriptorClassesTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInlineClassIncludeDescriptorClassesTest.java
index 8091d09..434d0df 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInlineClassIncludeDescriptorClassesTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInlineClassIncludeDescriptorClassesTest.java
@@ -16,8 +16,8 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.ToolHelper.ProcessResult;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.Matchers;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.Collection;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInlineClassTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInlineClassTest.java
index 8cc5eea..76b04a1 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInlineClassTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInlineClassTest.java
@@ -11,8 +11,8 @@
 import com.android.tools.r8.KotlinTestParameters;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.Collection;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInlinePropertyTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInlinePropertyTest.java
index 91e452b..cef3649 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInlinePropertyTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInlinePropertyTest.java
@@ -8,8 +8,8 @@
 import com.android.tools.r8.KotlinTestParameters;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.Collection;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInlineSuspendFunctionTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInlineSuspendFunctionTest.java
index b9b2530..4609a6d 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInlineSuspendFunctionTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInlineSuspendFunctionTest.java
@@ -8,9 +8,9 @@
 import com.android.tools.r8.KotlinCompilerTool.KotlinCompilerVersion;
 import com.android.tools.r8.KotlinTestParameters;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.internal.BooleanUtils;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.Collection;
 import org.junit.Assume;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInnerClassTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInnerClassTest.java
index 2d8dfd7..4be850d 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInnerClassTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteInnerClassTest.java
@@ -17,8 +17,8 @@
 import com.android.tools.r8.ProgramConsumer;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.Collection;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteJvmStaticTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteJvmStaticTest.java
index ee14002..4bd1c6a 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteJvmStaticTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteJvmStaticTest.java
@@ -14,13 +14,13 @@
 import com.android.tools.r8.kotlin.metadata.jvmstatic_app.MainJava;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.KmClassSubject;
 import com.android.tools.r8.utils.codeinspector.KmFunctionSubject;
 import com.android.tools.r8.utils.codeinspector.KmPropertySubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteLocalDelegatedPropertyTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteLocalDelegatedPropertyTest.java
index 812974f..97fa5d1 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteLocalDelegatedPropertyTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteLocalDelegatedPropertyTest.java
@@ -9,8 +9,8 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.Collection;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewritePrunedObjectsTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewritePrunedObjectsTest.java
index a05fbc0..b8355f4 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewritePrunedObjectsTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewritePrunedObjectsTest.java
@@ -15,10 +15,10 @@
 import com.android.tools.r8.KotlinTestParameters;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.KmClassSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.Collection;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteRawTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteRawTest.java
index e90c8ef..750b130 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteRawTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteRawTest.java
@@ -14,9 +14,9 @@
 import com.android.tools.r8.kotlin.metadata.type_raw_lib.JavaLibraryClass;
 import com.android.tools.r8.kotlin.metadata.type_raw_lib.JavaLibraryClass.GenericClass;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.ZipUtils.ZipBuilder;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.Collection;
 import org.junit.BeforeClass;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteRemovedCompanionTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteRemovedCompanionTest.java
index 5a71a59..04c7a5a 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteRemovedCompanionTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteRemovedCompanionTest.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.KotlinCompileMemoizer;
 import com.android.tools.r8.KotlinTestParameters;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.Collection;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteUnitPrimitiveTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteUnitPrimitiveTest.java
index d216d6f..e0d0006 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteUnitPrimitiveTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteUnitPrimitiveTest.java
@@ -12,8 +12,8 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.Collection;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteValueClassTest.java b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteValueClassTest.java
index 845e444..ec64e1c 100644
--- a/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteValueClassTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/metadata/MetadataRewriteValueClassTest.java
@@ -17,9 +17,9 @@
 import com.android.tools.r8.kotlin.KotlinMetadataWriter;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.nio.file.Path;
 import java.util.Collection;
diff --git a/src/test/java/com/android/tools/r8/kotlin/reflection/KotlinReflectTest.java b/src/test/java/com/android/tools/r8/kotlin/reflection/KotlinReflectTest.java
index b349e7c..61b4972 100644
--- a/src/test/java/com/android/tools/r8/kotlin/reflection/KotlinReflectTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/reflection/KotlinReflectTest.java
@@ -21,7 +21,7 @@
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.FileUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import java.io.File;
 import java.nio.file.Paths;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/kotlin/reflection/ReflectiveConstructionWithInlineClassTest.java b/src/test/java/com/android/tools/r8/kotlin/reflection/ReflectiveConstructionWithInlineClassTest.java
index f1f89b2..f51c19c 100644
--- a/src/test/java/com/android/tools/r8/kotlin/reflection/ReflectiveConstructionWithInlineClassTest.java
+++ b/src/test/java/com/android/tools/r8/kotlin/reflection/ReflectiveConstructionWithInlineClassTest.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.FileUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import java.nio.file.Paths;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/libcore/B369739225Test.java b/src/test/java/com/android/tools/r8/libcore/B369739225Test.java
index ee5fa8a..38790a3 100644
--- a/src/test/java/com/android/tools/r8/libcore/B369739225Test.java
+++ b/src/test/java/com/android/tools/r8/libcore/B369739225Test.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/locale/TurkishLocaleMultiReleaseJarTest.java b/src/test/java/com/android/tools/r8/locale/TurkishLocaleMultiReleaseJarTest.java
index 48f8121..ba89f57 100644
--- a/src/test/java/com/android/tools/r8/locale/TurkishLocaleMultiReleaseJarTest.java
+++ b/src/test/java/com/android/tools/r8/locale/TurkishLocaleMultiReleaseJarTest.java
@@ -14,9 +14,9 @@
 import com.android.tools.r8.ToolHelper.ArtCommandBuilder;
 import com.android.tools.r8.ToolHelper.ProcessResult;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.ZipUtils.ZipBuilder;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Path;
 import java.nio.file.Paths;
diff --git a/src/test/java/com/android/tools/r8/locale/TurkishLocaleZipFileInputTest.java b/src/test/java/com/android/tools/r8/locale/TurkishLocaleZipFileInputTest.java
index 4231616..cde68b6 100644
--- a/src/test/java/com/android/tools/r8/locale/TurkishLocaleZipFileInputTest.java
+++ b/src/test/java/com/android/tools/r8/locale/TurkishLocaleZipFileInputTest.java
@@ -14,9 +14,9 @@
 import com.android.tools.r8.ToolHelper.ArtCommandBuilder;
 import com.android.tools.r8.ToolHelper.ProcessResult;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.ZipUtils.ZipBuilder;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Path;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/maindexlist/MainDexDevirtualizerTest.java b/src/test/java/com/android/tools/r8/maindexlist/MainDexDevirtualizerTest.java
index 3320e1f..562e710 100644
--- a/src/test/java/com/android/tools/r8/maindexlist/MainDexDevirtualizerTest.java
+++ b/src/test/java/com/android/tools/r8/maindexlist/MainDexDevirtualizerTest.java
@@ -24,13 +24,13 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ThrowableConsumer;
 import com.android.tools.r8.ToolHelper;
-import com.android.tools.r8.utils.internal.Box;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CheckCastInstructionSubject;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.Box;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.function.BiConsumer;
diff --git a/src/test/java/com/android/tools/r8/maindexlist/MainDexListOutputTest.java b/src/test/java/com/android/tools/r8/maindexlist/MainDexListOutputTest.java
index 0649f9f..5b52873 100644
--- a/src/test/java/com/android/tools/r8/maindexlist/MainDexListOutputTest.java
+++ b/src/test/java/com/android/tools/r8/maindexlist/MainDexListOutputTest.java
@@ -23,9 +23,9 @@
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Path;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/maindexlist/MainDexListTests.java b/src/test/java/com/android/tools/r8/maindexlist/MainDexListTests.java
index 98a3739..da1a262 100644
--- a/src/test/java/com/android/tools/r8/maindexlist/MainDexListTests.java
+++ b/src/test/java/com/android/tools/r8/maindexlist/MainDexListTests.java
@@ -34,12 +34,12 @@
 import com.android.tools.r8.transformers.ClassTransformer;
 import com.android.tools.r8.utils.AndroidApp;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.ListUtils;
 import com.android.tools.r8.utils.MainDexListParser;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FoundClassSubject;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Lists;
 import java.io.IOException;
diff --git a/src/test/java/com/android/tools/r8/maindexlist/MainDexTracingTest.java b/src/test/java/com/android/tools/r8/maindexlist/MainDexTracingTest.java
index 7e51e8c..d909f22 100644
--- a/src/test/java/com/android/tools/r8/maindexlist/MainDexTracingTest.java
+++ b/src/test/java/com/android/tools/r8/maindexlist/MainDexTracingTest.java
@@ -5,9 +5,9 @@
 package com.android.tools.r8.maindexlist;
 
 import static com.android.tools.r8.synthesis.SyntheticItemsTestUtils.isLambdaMethodAnnotationDescriptor;
-import static com.android.tools.r8.utils.FileUtils.JAR_EXTENSION;
-import static com.android.tools.r8.utils.FileUtils.ZIP_EXTENSION;
-import static com.android.tools.r8.utils.FileUtils.withNativeFileSeparators;
+import static com.android.tools.r8.utils.internal.FileUtils.JAR_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.ZIP_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.withNativeFileSeparators;
 import static org.hamcrest.CoreMatchers.containsString;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.junit.Assert.assertArrayEquals;
@@ -28,10 +28,10 @@
 import com.android.tools.r8.shaking.WhyAreYouKeepingConsumer;
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.internal.Box;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.Box;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.io.PrintStream;
diff --git a/src/test/java/com/android/tools/r8/maindexlist/MainDexWithSynthesizedClassesTest.java b/src/test/java/com/android/tools/r8/maindexlist/MainDexWithSynthesizedClassesTest.java
index ca12f4d..278e14c 100644
--- a/src/test/java/com/android/tools/r8/maindexlist/MainDexWithSynthesizedClassesTest.java
+++ b/src/test/java/com/android/tools/r8/maindexlist/MainDexWithSynthesizedClassesTest.java
@@ -21,9 +21,9 @@
 import com.android.tools.r8.origin.PathOrigin;
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/maindexlist/whyareyoukeeping/MainDexListWhyAreYouKeeping.java b/src/test/java/com/android/tools/r8/maindexlist/whyareyoukeeping/MainDexListWhyAreYouKeeping.java
index e6aed45..21af62b 100644
--- a/src/test/java/com/android/tools/r8/maindexlist/whyareyoukeeping/MainDexListWhyAreYouKeeping.java
+++ b/src/test/java/com/android/tools/r8/maindexlist/whyareyoukeeping/MainDexListWhyAreYouKeeping.java
@@ -17,7 +17,7 @@
 import com.android.tools.r8.shaking.WhyAreYouKeepingConsumer;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.ListUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import com.google.common.collect.ImmutableList;
 import java.io.ByteArrayOutputStream;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeAlphaRenamingTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeAlphaRenamingTest.java
index e731ca0..1d86754 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeAlphaRenamingTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeAlphaRenamingTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeChangeLineNumberTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeChangeLineNumberTest.java
index ad3ab95..8f483db 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeChangeLineNumberTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeChangeLineNumberTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeChangeMethodAndLineNumberTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeChangeMethodAndLineNumberTest.java
index df197b8..0527903 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeChangeMethodAndLineNumberTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeChangeMethodAndLineNumberTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeChangeMethodTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeChangeMethodTest.java
index 05e04ff..433b55e 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeChangeMethodTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeChangeMethodTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeDifferentMethodTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeDifferentMethodTest.java
index ea5c219..3fbb0bc 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeDifferentMethodTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeDifferentMethodTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeDifferentMethodWithLineNumberTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeDifferentMethodWithLineNumberTest.java
index 132b0f5..99a5dfe 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeDifferentMethodWithLineNumberTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeDifferentMethodWithLineNumberTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeDistinctClassesTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeDistinctClassesTest.java
index 7dd7a45..f0baaae 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeDistinctClassesTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeDistinctClassesTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeDuplicateClassMappingTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeDuplicateClassMappingTest.java
index 7b92852..ad1cf36 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeDuplicateClassMappingTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeDuplicateClassMappingTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposeException;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeDuplicateMovedFieldTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeDuplicateMovedFieldTest.java
index 355dbf4..9bd1ad5 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeDuplicateMovedFieldTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeDuplicateMovedFieldTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeDuplicateOutlineTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeDuplicateOutlineTest.java
index 5c15d3d..64ba234 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeDuplicateOutlineTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeDuplicateOutlineTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runners.Parameterized.Parameter;
 import org.junit.runners.Parameterized.Parameters;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeFieldNameTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeFieldNameTest.java
index 70ad7e3..daa92d4 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeFieldNameTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeFieldNameTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeFieldWithAmbiguousTypeTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeFieldWithAmbiguousTypeTest.java
index 8ea3e2b..eb484b6 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeFieldWithAmbiguousTypeTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeFieldWithAmbiguousTypeTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeInlineFollowedByInlineTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeInlineFollowedByInlineTest.java
index fc1309a..cba2aa4 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeInlineFollowedByInlineTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeInlineFollowedByInlineTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeInlineFollowedByLineNumberChangeTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeInlineFollowedByLineNumberChangeTest.java
index ae082aa..08cf48c 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeInlineFollowedByLineNumberChangeTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeInlineFollowedByLineNumberChangeTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeInlineOfPositionsTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeInlineOfPositionsTest.java
index 90498fd..c724c5c 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeInlineOfPositionsTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeInlineOfPositionsTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeInlineOfPositionsThatViolateNewRangeTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeInlineOfPositionsThatViolateNewRangeTest.java
index ff4c376..282ae23 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeInlineOfPositionsThatViolateNewRangeTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeInlineOfPositionsThatViolateNewRangeTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeInlinePartialChangeTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeInlinePartialChangeTest.java
index 98aeb52..8db2b1d 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeInlinePartialChangeTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeInlinePartialChangeTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeInlineRangeOverlappingTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeInlineRangeOverlappingTest.java
index d966f3f..a6174f3 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeInlineRangeOverlappingTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeInlineRangeOverlappingTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeInlineResidualQualifiedTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeInlineResidualQualifiedTest.java
index 3b01b34..6f89c0b 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeInlineResidualQualifiedTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeInlineResidualQualifiedTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeMapVersionTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeMapVersionTest.java
index bfec642..29e0061 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeMapVersionTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeMapVersionTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposeException;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeMethodWithLineNumberRemovedTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeMethodWithLineNumberRemovedTest.java
index 9b28d99..533e314 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeMethodWithLineNumberRemovedTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeMethodWithLineNumberRemovedTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeMovedFieldTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeMovedFieldTest.java
index 69b78c7..25dc9fd 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeMovedFieldTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeMovedFieldTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeMovedMethodTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeMovedMethodTest.java
index 2991061..54f6657 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeMovedMethodTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeMovedMethodTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeMovedMethodWithPositionTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeMovedMethodWithPositionTest.java
index db17b8d..e33ea72 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeMovedMethodWithPositionTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeMovedMethodWithPositionTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeNoMinifiedPositionForMethodTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeNoMinifiedPositionForMethodTest.java
index de572a0..0b8fe2e 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeNoMinifiedPositionForMethodTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeNoMinifiedPositionForMethodTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeNoPositionForMethodTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeNoPositionForMethodTest.java
index ac8f21c..16f31ab 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeNoPositionForMethodTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeNoPositionForMethodTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeNoResidualSignatureExistingNamingLineNumberTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeNoResidualSignatureExistingNamingLineNumberTest.java
index 1799999..d56b70f 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeNoResidualSignatureExistingNamingLineNumberTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeNoResidualSignatureExistingNamingLineNumberTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeNoResidualSignatureExistingNamingTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeNoResidualSignatureExistingNamingTest.java
index 4b7e9a9..77352d5 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeNoResidualSignatureExistingNamingTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeNoResidualSignatureExistingNamingTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeOriginalViolatesNewRangeTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeOriginalViolatesNewRangeTest.java
index fe94d29..395cb7b 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeOriginalViolatesNewRangeTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeOriginalViolatesNewRangeTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeOutlineCallSiteInlinedTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeOutlineCallSiteInlinedTest.java
index df61bf9..f8358f6 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeOutlineCallSiteInlinedTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeOutlineCallSiteInlinedTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeOutlineHavingInlineInlinedTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeOutlineHavingInlineInlinedTest.java
index 301934c..83a0ebf 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeOutlineHavingInlineInlinedTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeOutlineHavingInlineInlinedTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runners.Parameterized.Parameter;
 import org.junit.runners.Parameterized.Parameters;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeOutlineInlineTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeOutlineInlineTest.java
index 0c50e79..a8d0896 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeOutlineInlineTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeOutlineInlineTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runners.Parameterized.Parameter;
 import org.junit.runners.Parameterized.Parameters;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeOutlineInlinedIntoOutlineAndInlinedTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeOutlineInlinedIntoOutlineAndInlinedTest.java
index 9dc41ea..cd57219 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeOutlineInlinedIntoOutlineAndInlinedTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeOutlineInlinedIntoOutlineAndInlinedTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runners.Parameterized.Parameter;
 import org.junit.runners.Parameterized.Parameters;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeOutlinePositionRangeTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeOutlinePositionRangeTest.java
index 753f3d7..5d8da1a 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeOutlinePositionRangeTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeOutlinePositionRangeTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeOutlineTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeOutlineTest.java
index 98ba4d5..a1c548b 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeOutlineTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeOutlineTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeOutlineWithIdRangeTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeOutlineWithIdRangeTest.java
index e79ad2c..59af52c 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeOutlineWithIdRangeTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeOutlineWithIdRangeTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runners.Parameterized.Parameter;
 import org.junit.runners.Parameterized.Parameters;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeOutlineWithRangeTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeOutlineWithRangeTest.java
index 1e846e1..c0720c0 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeOutlineWithRangeTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeOutlineWithRangeTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeOverloadSameRangeTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeOverloadSameRangeTest.java
index a81af5d..95c4696 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeOverloadSameRangeTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeOverloadSameRangeTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposePreambleCommentTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposePreambleCommentTest.java
index a5795d3..edcbd04 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposePreambleCommentTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposePreambleCommentTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposePreambleSyntheticTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposePreambleSyntheticTest.java
index aab1805..7e12ab1 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposePreambleSyntheticTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposePreambleSyntheticTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposePreambleTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposePreambleTest.java
index f9a16e8..421e5d7 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposePreambleTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposePreambleTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeRewriteFrameTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeRewriteFrameTest.java
index 93a9153..a486d21 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeRewriteFrameTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeRewriteFrameTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeSourceFileTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeSourceFileTest.java
index 434c494..d27d6de 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeSourceFileTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeSourceFileTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeSplitRangeStartTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeSplitRangeStartTest.java
index 0903712..c5e5496 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeSplitRangeStartTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeSplitRangeStartTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeSyntheticTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeSyntheticTest.java
index 0954d3a..aa5a49d 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeSyntheticTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeSyntheticTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeUnknownJsonD8Test.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeUnknownJsonD8Test.java
index e36810c..26960fc 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeUnknownJsonD8Test.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeUnknownJsonD8Test.java
@@ -19,7 +19,7 @@
 import com.android.tools.r8.retrace.PartitionMappingSupplier;
 import com.android.tools.r8.retrace.PartitionedToProguardMappingConverter;
 import com.android.tools.r8.utils.internal.Box;
-import com.android.tools.r8.utils.FileUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import java.nio.file.Path;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeUnknownJsonTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeUnknownJsonTest.java
index 022f42f..ab4b460 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeUnknownJsonTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeUnknownJsonTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeWithHolesTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeWithHolesTest.java
index 2445d9c..e7793e9 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeWithHolesTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeWithHolesTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ClassNameMapper;
 import com.android.tools.r8.naming.MappingComposer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/mappingcompose/ComposeWithMissingDebugInfoTest.java b/src/test/java/com/android/tools/r8/mappingcompose/ComposeWithMissingDebugInfoTest.java
index 02d145d..5013bca 100644
--- a/src/test/java/com/android/tools/r8/mappingcompose/ComposeWithMissingDebugInfoTest.java
+++ b/src/test/java/com/android/tools/r8/mappingcompose/ComposeWithMissingDebugInfoTest.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.retrace.ProguardMapProducer;
 import com.android.tools.r8.retrace.ProguardMappingSupplier;
 import com.android.tools.r8.transformers.ClassFileTransformer.MethodPredicate;
-import com.android.tools.r8.utils.FileUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import java.nio.file.Path;
 import java.util.ArrayList;
 import java.util.HashSet;
diff --git a/src/test/java/com/android/tools/r8/memberrebinding/IllegalFieldRebindingTest.java b/src/test/java/com/android/tools/r8/memberrebinding/IllegalFieldRebindingTest.java
index 841cc0f..544b3cf 100644
--- a/src/test/java/com/android/tools/r8/memberrebinding/IllegalFieldRebindingTest.java
+++ b/src/test/java/com/android/tools/r8/memberrebinding/IllegalFieldRebindingTest.java
@@ -13,11 +13,11 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.memberrebinding.testclasses.IllegalFieldRebindingTestClasses;
 import com.android.tools.r8.memberrebinding.testclasses.IllegalFieldRebindingTestClasses.B;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/memberrebinding/IndirectSuperInterfaceTest.java b/src/test/java/com/android/tools/r8/memberrebinding/IndirectSuperInterfaceTest.java
index 0d4f532..6d9064a 100644
--- a/src/test/java/com/android/tools/r8/memberrebinding/IndirectSuperInterfaceTest.java
+++ b/src/test/java/com/android/tools/r8/memberrebinding/IndirectSuperInterfaceTest.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/memberrebinding/LibraryMemberRebindingSuperTest.java b/src/test/java/com/android/tools/r8/memberrebinding/LibraryMemberRebindingSuperTest.java
index bd2532d..ed0d6e5 100644
--- a/src/test/java/com/android/tools/r8/memberrebinding/LibraryMemberRebindingSuperTest.java
+++ b/src/test/java/com/android/tools/r8/memberrebinding/LibraryMemberRebindingSuperTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.apimodel.ApiModelingTestHelper;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/memberrebinding/MemberRebindingBridgeRemovalTest.java b/src/test/java/com/android/tools/r8/memberrebinding/MemberRebindingBridgeRemovalTest.java
index 54600ce..d2bfc42 100644
--- a/src/test/java/com/android/tools/r8/memberrebinding/MemberRebindingBridgeRemovalTest.java
+++ b/src/test/java/com/android/tools/r8/memberrebinding/MemberRebindingBridgeRemovalTest.java
@@ -14,10 +14,10 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.memberrebinding.testclasses.MemberRebindingBridgeRemovalTestClasses;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FoundMethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/memberrebinding/MemberRebindingInterfaceHierachyDefaultTest.java b/src/test/java/com/android/tools/r8/memberrebinding/MemberRebindingInterfaceHierachyDefaultTest.java
index f124802..51cba73 100644
--- a/src/test/java/com/android/tools/r8/memberrebinding/MemberRebindingInterfaceHierachyDefaultTest.java
+++ b/src/test/java/com/android/tools/r8/memberrebinding/MemberRebindingInterfaceHierachyDefaultTest.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestShrinkerBuilder;
 import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/memberrebinding/protectedaccess/MemberRebindingProtectedInLibraryHierarchyTest.java b/src/test/java/com/android/tools/r8/memberrebinding/protectedaccess/MemberRebindingProtectedInLibraryHierarchyTest.java
index de3d6bb..47d78fd 100644
--- a/src/test/java/com/android/tools/r8/memberrebinding/protectedaccess/MemberRebindingProtectedInLibraryHierarchyTest.java
+++ b/src/test/java/com/android/tools/r8/memberrebinding/protectedaccess/MemberRebindingProtectedInLibraryHierarchyTest.java
@@ -8,9 +8,9 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.InvokeInstructionSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.LinkedHashMap;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/memberrebinding/protectedaccess/MemberRebindingProtectedInProgramHierachyTest.java b/src/test/java/com/android/tools/r8/memberrebinding/protectedaccess/MemberRebindingProtectedInProgramHierachyTest.java
index 962517f..2cf9f3e 100644
--- a/src/test/java/com/android/tools/r8/memberrebinding/protectedaccess/MemberRebindingProtectedInProgramHierachyTest.java
+++ b/src/test/java/com/android/tools/r8/memberrebinding/protectedaccess/MemberRebindingProtectedInProgramHierachyTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.memberrebinding.protectedaccess.util.A;
 import com.android.tools.r8.memberrebinding.protectedaccess.util.B;
 import com.android.tools.r8.memberrebinding.protectedaccess.util.Base;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/metadata/D8BuildMetadataTest.java b/src/test/java/com/android/tools/r8/metadata/D8BuildMetadataTest.java
index 18fdcd1..375b09b 100644
--- a/src/test/java/com/android/tools/r8/metadata/D8BuildMetadataTest.java
+++ b/src/test/java/com/android/tools/r8/metadata/D8BuildMetadataTest.java
@@ -20,7 +20,7 @@
 import com.android.tools.r8.Version;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.origin.EmbeddedOrigin;
-import com.android.tools.r8.utils.FileUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import java.nio.file.Path;
 import java.util.Arrays;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/naming/AbstractMethodRenamingTest.java b/src/test/java/com/android/tools/r8/naming/AbstractMethodRenamingTest.java
index 7776f15..ca2d125 100644
--- a/src/test/java/com/android/tools/r8/naming/AbstractMethodRenamingTest.java
+++ b/src/test/java/com/android/tools/r8/naming/AbstractMethodRenamingTest.java
@@ -12,10 +12,10 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/naming/AdaptResourceFileContentsTest.java b/src/test/java/com/android/tools/r8/naming/AdaptResourceFileContentsTest.java
index 0657cc6..8a04ae3b 100644
--- a/src/test/java/com/android/tools/r8/naming/AdaptResourceFileContentsTest.java
+++ b/src/test/java/com/android/tools/r8/naming/AdaptResourceFileContentsTest.java
@@ -4,8 +4,8 @@
 
 package com.android.tools.r8.naming;
 
-import static com.android.tools.r8.utils.StringUtils.UNIX_LINE_SEPARATOR;
 import static com.android.tools.r8.utils.codeinspector.Matchers.isPresent;
+import static com.android.tools.r8.utils.internal.StringUtils.UNIX_LINE_SEPARATOR;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertNotEquals;
diff --git a/src/test/java/com/android/tools/r8/naming/AdaptResourceFileNamesTest.java b/src/test/java/com/android/tools/r8/naming/AdaptResourceFileNamesTest.java
index 6344284..2e3678a 100644
--- a/src/test/java/com/android/tools/r8/naming/AdaptResourceFileNamesTest.java
+++ b/src/test/java/com/android/tools/r8/naming/AdaptResourceFileNamesTest.java
@@ -21,7 +21,7 @@
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.shaking.forceproguardcompatibility.ProguardCompatibilityTestBase;
 import com.android.tools.r8.utils.DataResourceConsumerForTesting;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/naming/AvoidRTest.java b/src/test/java/com/android/tools/r8/naming/AvoidRTest.java
index 1ba1043..87722c2 100644
--- a/src/test/java/com/android/tools/r8/naming/AvoidRTest.java
+++ b/src/test/java/com/android/tools/r8/naming/AvoidRTest.java
@@ -14,8 +14,8 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.jasmin.JasminBuilder;
 import com.android.tools.r8.jasmin.JasminTestBase;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableSet;
 import java.nio.file.Path;
 import java.util.HashSet;
diff --git a/src/test/java/com/android/tools/r8/naming/ClassNameMinifierOriginalClassNameTest.java b/src/test/java/com/android/tools/r8/naming/ClassNameMinifierOriginalClassNameTest.java
index 49ebe1a..1a526ea 100644
--- a/src/test/java/com/android/tools/r8/naming/ClassNameMinifierOriginalClassNameTest.java
+++ b/src/test/java/com/android/tools/r8/naming/ClassNameMinifierOriginalClassNameTest.java
@@ -18,7 +18,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.testclasses.A;
 import com.android.tools.r8.naming.testclasses.B;
-import com.android.tools.r8.utils.FileUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import java.io.IOException;
 import java.nio.file.Path;
 import java.util.concurrent.ExecutionException;
diff --git a/src/test/java/com/android/tools/r8/naming/ClassObfuscationDictionaryDuplicateTest.java b/src/test/java/com/android/tools/r8/naming/ClassObfuscationDictionaryDuplicateTest.java
index da59930..6ea6ace 100644
--- a/src/test/java/com/android/tools/r8/naming/ClassObfuscationDictionaryDuplicateTest.java
+++ b/src/test/java/com/android/tools/r8/naming/ClassObfuscationDictionaryDuplicateTest.java
@@ -13,8 +13,8 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
+import com.android.tools.r8.utils.internal.FileUtils;
 import java.io.IOException;
 import java.nio.file.Path;
 import java.util.concurrent.ExecutionException;
diff --git a/src/test/java/com/android/tools/r8/naming/DontUseMixedCaseClassNamesExistingClassTest.java b/src/test/java/com/android/tools/r8/naming/DontUseMixedCaseClassNamesExistingClassTest.java
index f2bb59c..248e24d 100644
--- a/src/test/java/com/android/tools/r8/naming/DontUseMixedCaseClassNamesExistingClassTest.java
+++ b/src/test/java/com/android/tools/r8/naming/DontUseMixedCaseClassNamesExistingClassTest.java
@@ -11,8 +11,8 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.nio.file.Path;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/naming/FieldMinificationCollisionTest.java b/src/test/java/com/android/tools/r8/naming/FieldMinificationCollisionTest.java
index d8e0168..532bc82 100644
--- a/src/test/java/com/android/tools/r8/naming/FieldMinificationCollisionTest.java
+++ b/src/test/java/com/android/tools/r8/naming/FieldMinificationCollisionTest.java
@@ -13,9 +13,9 @@
 import com.android.tools.r8.NeverPropagateValue;
 import com.android.tools.r8.NoVerticalClassMerging;
 import com.android.tools.r8.TestBase;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FieldSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 
 /** Regression test for b/127932803. */
diff --git a/src/test/java/com/android/tools/r8/naming/FieldMinificationObfuscationDictionaryDuplicateTest.java b/src/test/java/com/android/tools/r8/naming/FieldMinificationObfuscationDictionaryDuplicateTest.java
index 28a0ba9..b68f42c 100644
--- a/src/test/java/com/android/tools/r8/naming/FieldMinificationObfuscationDictionaryDuplicateTest.java
+++ b/src/test/java/com/android/tools/r8/naming/FieldMinificationObfuscationDictionaryDuplicateTest.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.FileUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import java.io.IOException;
 import java.nio.file.Path;
 import java.util.concurrent.ExecutionException;
diff --git a/src/test/java/com/android/tools/r8/naming/IdentifierMinifierTest.java b/src/test/java/com/android/tools/r8/naming/IdentifierMinifierTest.java
index 05bea2e..194373b 100644
--- a/src/test/java/com/android/tools/r8/naming/IdentifierMinifierTest.java
+++ b/src/test/java/com/android/tools/r8/naming/IdentifierMinifierTest.java
@@ -15,7 +15,6 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.graph.DexEncodedField;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.ListUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
@@ -23,6 +22,7 @@
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject.JumboStringMode;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.collect.Sets;
 import java.nio.file.Paths;
 import java.util.ArrayList;
diff --git a/src/test/java/com/android/tools/r8/naming/IdentityMappingFileTest.java b/src/test/java/com/android/tools/r8/naming/IdentityMappingFileTest.java
index 49c417b..9b73a61 100644
--- a/src/test/java/com/android/tools/r8/naming/IdentityMappingFileTest.java
+++ b/src/test/java/com/android/tools/r8/naming/IdentityMappingFileTest.java
@@ -21,8 +21,8 @@
 import com.android.tools.r8.transformers.ClassFileTransformer.MethodPredicate;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.internal.BooleanBox;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
diff --git a/src/test/java/com/android/tools/r8/naming/InterfaceConstructorRenamingTest.java b/src/test/java/com/android/tools/r8/naming/InterfaceConstructorRenamingTest.java
index 0b6f53f..55350ef 100644
--- a/src/test/java/com/android/tools/r8/naming/InterfaceConstructorRenamingTest.java
+++ b/src/test/java/com/android/tools/r8/naming/InterfaceConstructorRenamingTest.java
@@ -12,8 +12,8 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.util.Collections;
 import java.util.function.Function;
diff --git a/src/test/java/com/android/tools/r8/naming/InterfaceFieldMinificationTest.java b/src/test/java/com/android/tools/r8/naming/InterfaceFieldMinificationTest.java
index ad294d3..025a492 100644
--- a/src/test/java/com/android/tools/r8/naming/InterfaceFieldMinificationTest.java
+++ b/src/test/java/com/android/tools/r8/naming/InterfaceFieldMinificationTest.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.testclasses.Greeting;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/naming/InterfaceMethodNameMinifierTest.java b/src/test/java/com/android/tools/r8/naming/InterfaceMethodNameMinifierTest.java
index a853b95..1cb3807 100644
--- a/src/test/java/com/android/tools/r8/naming/InterfaceMethodNameMinifierTest.java
+++ b/src/test/java/com/android/tools/r8/naming/InterfaceMethodNameMinifierTest.java
@@ -6,7 +6,7 @@
 
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.graph.DexMethod;
-import com.android.tools.r8.utils.FileUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import java.nio.file.Path;
 import org.junit.Test;
 
diff --git a/src/test/java/com/android/tools/r8/naming/InvalidObfuscationEntryTest.java b/src/test/java/com/android/tools/r8/naming/InvalidObfuscationEntryTest.java
index 29cfe82..f360e6c 100644
--- a/src/test/java/com/android/tools/r8/naming/InvalidObfuscationEntryTest.java
+++ b/src/test/java/com/android/tools/r8/naming/InvalidObfuscationEntryTest.java
@@ -14,9 +14,9 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.FileUtils;
 import java.io.IOException;
 import java.nio.file.Path;
 import java.util.concurrent.ExecutionException;
diff --git a/src/test/java/com/android/tools/r8/naming/KotlinIntrinsicsIdentifierTest.java b/src/test/java/com/android/tools/r8/naming/KotlinIntrinsicsIdentifierTest.java
index 508cfad..f4b6708 100644
--- a/src/test/java/com/android/tools/r8/naming/KotlinIntrinsicsIdentifierTest.java
+++ b/src/test/java/com/android/tools/r8/naming/KotlinIntrinsicsIdentifierTest.java
@@ -20,13 +20,13 @@
 import com.android.tools.r8.kotlin.TestKotlinClass;
 import com.android.tools.r8.shaking.NoHorizontalClassMergingRule;
 import com.android.tools.r8.shaking.NoVerticalClassMergingRule;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject.JumboStringMode;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.Iterator;
diff --git a/src/test/java/com/android/tools/r8/naming/LambdaRenamingTestRunner.java b/src/test/java/com/android/tools/r8/naming/LambdaRenamingTestRunner.java
index 7f09c2e..f97d5dd 100644
--- a/src/test/java/com/android/tools/r8/naming/LambdaRenamingTestRunner.java
+++ b/src/test/java/com/android/tools/r8/naming/LambdaRenamingTestRunner.java
@@ -3,9 +3,6 @@
 // BSD-style license that can be found in the LICENSE file.
 package com.android.tools.r8.naming;
 
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertNotEquals;
-import static org.junit.Assume.assumeTrue;
 
 import com.android.tools.r8.ByteDataView;
 import com.android.tools.r8.ClassFileConsumer.ArchiveConsumer;
@@ -13,10 +10,8 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ToolHelper;
-import com.android.tools.r8.ToolHelper.ProcessResult;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.nio.file.Path;
 import org.junit.Before;
diff --git a/src/test/java/com/android/tools/r8/naming/MapReaderVersionTest.java b/src/test/java/com/android/tools/r8/naming/MapReaderVersionTest.java
index d1991df..d7b9dd8 100644
--- a/src/test/java/com/android/tools/r8/naming/MapReaderVersionTest.java
+++ b/src/test/java/com/android/tools/r8/naming/MapReaderVersionTest.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.mappinginformation.MappingInformation;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.io.CharSource;
 import java.io.IOException;
 import org.junit.Assert;
diff --git a/src/test/java/com/android/tools/r8/naming/MappingHeaderContentTest.java b/src/test/java/com/android/tools/r8/naming/MappingHeaderContentTest.java
index 7046df6..7e403fe 100644
--- a/src/test/java/com/android/tools/r8/naming/MappingHeaderContentTest.java
+++ b/src/test/java/com/android/tools/r8/naming/MappingHeaderContentTest.java
@@ -17,7 +17,7 @@
 import com.android.tools.r8.retrace.MappingPartitionMetadata;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.internal.Box;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.stream.Collectors;
diff --git a/src/test/java/com/android/tools/r8/naming/NonMemberClassTest.java b/src/test/java/com/android/tools/r8/naming/NonMemberClassTest.java
index 38186ee..e80942d 100644
--- a/src/test/java/com/android/tools/r8/naming/NonMemberClassTest.java
+++ b/src/test/java/com/android/tools/r8/naming/NonMemberClassTest.java
@@ -10,8 +10,8 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestRuntime.CfVm;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import java.util.Collection;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/naming/ObfuscationDictionaryDuplicateTest.java b/src/test/java/com/android/tools/r8/naming/ObfuscationDictionaryDuplicateTest.java
index e7babea..95bce09 100644
--- a/src/test/java/com/android/tools/r8/naming/ObfuscationDictionaryDuplicateTest.java
+++ b/src/test/java/com/android/tools/r8/naming/ObfuscationDictionaryDuplicateTest.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.FileUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import java.io.IOException;
 import java.nio.file.Path;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/naming/ObfuscationPrimitiveNamesTest.java b/src/test/java/com/android/tools/r8/naming/ObfuscationPrimitiveNamesTest.java
index a9821f4..9e0a197 100644
--- a/src/test/java/com/android/tools/r8/naming/ObfuscationPrimitiveNamesTest.java
+++ b/src/test/java/com/android/tools/r8/naming/ObfuscationPrimitiveNamesTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.FileUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.collect.Lists;
 import java.nio.file.Path;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/naming/OverloadedReservedFieldNamingTest.java b/src/test/java/com/android/tools/r8/naming/OverloadedReservedFieldNamingTest.java
index af32058..b282617 100644
--- a/src/test/java/com/android/tools/r8/naming/OverloadedReservedFieldNamingTest.java
+++ b/src/test/java/com/android/tools/r8/naming/OverloadedReservedFieldNamingTest.java
@@ -14,10 +14,10 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.references.Reference;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FieldSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/naming/PackageObfuscationDictionaryDuplicateTest.java b/src/test/java/com/android/tools/r8/naming/PackageObfuscationDictionaryDuplicateTest.java
index 86ebc79..f1d8ac0 100644
--- a/src/test/java/com/android/tools/r8/naming/PackageObfuscationDictionaryDuplicateTest.java
+++ b/src/test/java/com/android/tools/r8/naming/PackageObfuscationDictionaryDuplicateTest.java
@@ -12,8 +12,8 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.keeppackagenames.Top;
 import com.android.tools.r8.naming.packageobfuscationdict.A;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
+import com.android.tools.r8.utils.internal.FileUtils;
 import java.io.IOException;
 import java.nio.file.Path;
 import java.util.concurrent.ExecutionException;
diff --git a/src/test/java/com/android/tools/r8/naming/ProgramTypeRenamedAsClasspathTypeTest.java b/src/test/java/com/android/tools/r8/naming/ProgramTypeRenamedAsClasspathTypeTest.java
index 4be52fb..486d880 100644
--- a/src/test/java/com/android/tools/r8/naming/ProgramTypeRenamedAsClasspathTypeTest.java
+++ b/src/test/java/com/android/tools/r8/naming/ProgramTypeRenamedAsClasspathTypeTest.java
@@ -12,8 +12,8 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.FoundClassSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.HashSet;
 import java.util.Set;
diff --git a/src/test/java/com/android/tools/r8/naming/ProguardMapReaderArgumentsTest.java b/src/test/java/com/android/tools/r8/naming/ProguardMapReaderArgumentsTest.java
index 8e91ae1..18051ce 100644
--- a/src/test/java/com/android/tools/r8/naming/ProguardMapReaderArgumentsTest.java
+++ b/src/test/java/com/android/tools/r8/naming/ProguardMapReaderArgumentsTest.java
@@ -17,7 +17,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.mappinginformation.MappingInformationDiagnostics;
 import com.android.tools.r8.utils.Reporter;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/naming/ProguardMapReaderPackageInfoTest.java b/src/test/java/com/android/tools/r8/naming/ProguardMapReaderPackageInfoTest.java
index 9f172e3..b8ff1f9 100644
--- a/src/test/java/com/android/tools/r8/naming/ProguardMapReaderPackageInfoTest.java
+++ b/src/test/java/com/android/tools/r8/naming/ProguardMapReaderPackageInfoTest.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/naming/ProguardMapReaderTest.java b/src/test/java/com/android/tools/r8/naming/ProguardMapReaderTest.java
index b6ef1a4..ff5685e 100644
--- a/src/test/java/com/android/tools/r8/naming/ProguardMapReaderTest.java
+++ b/src/test/java/com/android/tools/r8/naming/ProguardMapReaderTest.java
@@ -16,8 +16,8 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.ProguardMapReader.ParseException;
 import com.android.tools.r8.position.Position;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.nio.file.Files;
diff --git a/src/test/java/com/android/tools/r8/naming/ReservedFieldNameInInterfacesWithCommonSubClassTest.java b/src/test/java/com/android/tools/r8/naming/ReservedFieldNameInInterfacesWithCommonSubClassTest.java
index 9f9b81f..e5000dc 100644
--- a/src/test/java/com/android/tools/r8/naming/ReservedFieldNameInInterfacesWithCommonSubClassTest.java
+++ b/src/test/java/com/android/tools/r8/naming/ReservedFieldNameInInterfacesWithCommonSubClassTest.java
@@ -12,11 +12,11 @@
 
 import com.android.tools.r8.NoVerticalClassMerging;
 import com.android.tools.r8.TestBase;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FieldSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/naming/ReservedFieldNameInSubClassTest.java b/src/test/java/com/android/tools/r8/naming/ReservedFieldNameInSubClassTest.java
index a010d9b..96bdbbd 100644
--- a/src/test/java/com/android/tools/r8/naming/ReservedFieldNameInSubClassTest.java
+++ b/src/test/java/com/android/tools/r8/naming/ReservedFieldNameInSubClassTest.java
@@ -13,11 +13,11 @@
 import com.android.tools.r8.NoVerticalClassMerging;
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FieldSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/naming/ReservedFieldNameInSubInterfaceTest.java b/src/test/java/com/android/tools/r8/naming/ReservedFieldNameInSubInterfaceTest.java
index 0a38bad..12563d4 100644
--- a/src/test/java/com/android/tools/r8/naming/ReservedFieldNameInSubInterfaceTest.java
+++ b/src/test/java/com/android/tools/r8/naming/ReservedFieldNameInSubInterfaceTest.java
@@ -14,11 +14,11 @@
 import com.android.tools.r8.NoVerticalClassMerging;
 import com.android.tools.r8.R8TestRunResult;
 import com.android.tools.r8.TestBase;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FieldSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/naming/ReservedFieldNameInSuperClassTest.java b/src/test/java/com/android/tools/r8/naming/ReservedFieldNameInSuperClassTest.java
index e425b34..8559050 100644
--- a/src/test/java/com/android/tools/r8/naming/ReservedFieldNameInSuperClassTest.java
+++ b/src/test/java/com/android/tools/r8/naming/ReservedFieldNameInSuperClassTest.java
@@ -13,11 +13,11 @@
 
 import com.android.tools.r8.NoHorizontalClassMerging;
 import com.android.tools.r8.TestBase;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FieldSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/naming/ReservedFieldNameInSuperInterfaceTest.java b/src/test/java/com/android/tools/r8/naming/ReservedFieldNameInSuperInterfaceTest.java
index 43cbd02..e12bb9d 100644
--- a/src/test/java/com/android/tools/r8/naming/ReservedFieldNameInSuperInterfaceTest.java
+++ b/src/test/java/com/android/tools/r8/naming/ReservedFieldNameInSuperInterfaceTest.java
@@ -13,11 +13,11 @@
 import com.android.tools.r8.NeverPropagateValue;
 import com.android.tools.r8.R8TestRunResult;
 import com.android.tools.r8.TestBase;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FieldSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/naming/SeedMapperTests.java b/src/test/java/com/android/tools/r8/naming/SeedMapperTests.java
index 31e8267..895964b 100644
--- a/src/test/java/com/android/tools/r8/naming/SeedMapperTests.java
+++ b/src/test/java/com/android/tools/r8/naming/SeedMapperTests.java
@@ -13,8 +13,8 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.utils.AbortException;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.Reporter;
+import com.android.tools.r8.utils.internal.FileUtils;
 import java.io.IOException;
 import java.nio.file.Path;
 import org.junit.Ignore;
diff --git a/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingAfterDevirtualizationTest.java b/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingAfterDevirtualizationTest.java
index 319c4e8..6340a0b 100644
--- a/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingAfterDevirtualizationTest.java
+++ b/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingAfterDevirtualizationTest.java
@@ -14,8 +14,8 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingAfterHorizontalMergingFieldTest.java b/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingAfterHorizontalMergingFieldTest.java
index 04f428d..1e0252d 100644
--- a/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingAfterHorizontalMergingFieldTest.java
+++ b/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingAfterHorizontalMergingFieldTest.java
@@ -11,8 +11,8 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingAfterHorizontalMergingMethodTest.java b/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingAfterHorizontalMergingMethodTest.java
index 38b04ec..3ac372b 100644
--- a/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingAfterHorizontalMergingMethodTest.java
+++ b/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingAfterHorizontalMergingMethodTest.java
@@ -13,8 +13,8 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingAfterVerticalMergingFieldTest.java b/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingAfterVerticalMergingFieldTest.java
index 139eae6..d4f3796 100644
--- a/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingAfterVerticalMergingFieldTest.java
+++ b/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingAfterVerticalMergingFieldTest.java
@@ -11,8 +11,8 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingAfterVerticalMergingMethodTest.java b/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingAfterVerticalMergingMethodTest.java
index 80bc496..7587de79 100644
--- a/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingAfterVerticalMergingMethodTest.java
+++ b/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingAfterVerticalMergingMethodTest.java
@@ -16,8 +16,8 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.FoundMethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.nio.file.Path;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingDesugarLambdaTest.java b/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingDesugarLambdaTest.java
index 0dfe291..4bffd00 100644
--- a/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingDesugarLambdaTest.java
+++ b/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingDesugarLambdaTest.java
@@ -14,8 +14,8 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.codeinspector.FoundClassSubject;
+import com.android.tools.r8.utils.internal.FileUtils;
 import java.io.IOException;
 import java.nio.file.Path;
 import java.util.concurrent.ExecutionException;
diff --git a/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingInterfaceClInitTest.java b/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingInterfaceClInitTest.java
index 97360c0..32183b8 100644
--- a/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingInterfaceClInitTest.java
+++ b/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingInterfaceClInitTest.java
@@ -12,9 +12,9 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.util.concurrent.ExecutionException;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingMinificationTest.java b/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingMinificationTest.java
index e6ae679..6d1f240 100644
--- a/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingMinificationTest.java
+++ b/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingMinificationTest.java
@@ -18,10 +18,10 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.FieldSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.util.concurrent.ExecutionException;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingMovedMethodTest.java b/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingMovedMethodTest.java
index 2c2b6af..024b857 100644
--- a/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingMovedMethodTest.java
+++ b/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingMovedMethodTest.java
@@ -14,9 +14,9 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.MemberSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.Iterables;
 import java.util.HashSet;
 import java.util.Set;
diff --git a/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingNonMemberClassTest.java b/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingNonMemberClassTest.java
index c1a81d8..ae96e27 100644
--- a/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingNonMemberClassTest.java
+++ b/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingNonMemberClassTest.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingRepackagingTest.java b/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingRepackagingTest.java
index 9fe05b4..6df0c23 100644
--- a/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingRepackagingTest.java
+++ b/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingRepackagingTest.java
@@ -17,10 +17,10 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.FieldSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.util.concurrent.ExecutionException;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingRotateNameClashTest.java b/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingRotateNameClashTest.java
index 81ba247..df79480 100644
--- a/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingRotateNameClashTest.java
+++ b/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingRotateNameClashTest.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.util.concurrent.ExecutionException;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingSameStaticNameTest.java b/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingSameStaticNameTest.java
index 71e101a..809bbae 100644
--- a/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingSameStaticNameTest.java
+++ b/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingSameStaticNameTest.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingVirtualInvokeTest.java b/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingVirtualInvokeTest.java
index 3e4723a..c0d592a 100644
--- a/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingVirtualInvokeTest.java
+++ b/src/test/java/com/android/tools/r8/naming/applymapping/ApplyMappingVirtualInvokeTest.java
@@ -15,7 +15,7 @@
 import com.android.tools.r8.naming.applymapping.ApplyMappingVirtualInvokeTest.TestClasses.LibrarySubclass;
 import com.android.tools.r8.naming.applymapping.ApplyMappingVirtualInvokeTest.TestClasses.ProgramClass;
 import com.android.tools.r8.naming.applymapping.ApplyMappingVirtualInvokeTest.TestClasses.ProgramSubclass;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.util.concurrent.ExecutionException;
 import java.util.function.Function;
diff --git a/src/test/java/com/android/tools/r8/naming/applymapping/desugar/DefaultInterfaceMethodTest.java b/src/test/java/com/android/tools/r8/naming/applymapping/desugar/DefaultInterfaceMethodTest.java
index 8a694dc..fecfe66 100644
--- a/src/test/java/com/android/tools/r8/naming/applymapping/desugar/DefaultInterfaceMethodTest.java
+++ b/src/test/java/com/android/tools/r8/naming/applymapping/desugar/DefaultInterfaceMethodTest.java
@@ -15,8 +15,8 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/naming/applymapping/desugar/StaticInterfaceMethodTest.java b/src/test/java/com/android/tools/r8/naming/applymapping/desugar/StaticInterfaceMethodTest.java
index 5f6aad0..701c1df 100644
--- a/src/test/java/com/android/tools/r8/naming/applymapping/desugar/StaticInterfaceMethodTest.java
+++ b/src/test/java/com/android/tools/r8/naming/applymapping/desugar/StaticInterfaceMethodTest.java
@@ -14,10 +14,9 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.naming.applymapping.desugar.DefaultInterfaceMethodTest.LibraryInterface;
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/naming/applymapping/shared/NameClashTest.java b/src/test/java/com/android/tools/r8/naming/applymapping/shared/NameClashTest.java
index 97f2633..f7ae149 100644
--- a/src/test/java/com/android/tools/r8/naming/applymapping/shared/NameClashTest.java
+++ b/src/test/java/com/android/tools/r8/naming/applymapping/shared/NameClashTest.java
@@ -13,8 +13,8 @@
 import com.android.tools.r8.naming.applymapping.shared.ProgramWithLibraryClasses.AnotherLibraryClass;
 import com.android.tools.r8.naming.applymapping.shared.ProgramWithLibraryClasses.LibraryClass;
 import com.android.tools.r8.naming.applymapping.shared.ProgramWithLibraryClasses.ProgramClass;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Path;
 import org.junit.Before;
diff --git a/src/test/java/com/android/tools/r8/naming/applymapping/sourcelibrary/ApplyMappingTest.java b/src/test/java/com/android/tools/r8/naming/applymapping/sourcelibrary/ApplyMappingTest.java
index 223b45c..42cd6bf 100644
--- a/src/test/java/com/android/tools/r8/naming/applymapping/sourcelibrary/ApplyMappingTest.java
+++ b/src/test/java/com/android/tools/r8/naming/applymapping/sourcelibrary/ApplyMappingTest.java
@@ -16,13 +16,13 @@
 import com.android.tools.r8.graph.DexMethod;
 import com.android.tools.r8.graph.DexType;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.InvokeInstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
 import com.android.tools.r8.utils.codeinspector.NewInstanceInstructionSubject;
+import com.android.tools.r8.utils.internal.FileUtils;
 import java.nio.file.Path;
 import java.nio.file.Paths;
 import java.util.Iterator;
diff --git a/src/test/java/com/android/tools/r8/naming/applymapping/sourcelibrary/InnerEnumValuesTest.java b/src/test/java/com/android/tools/r8/naming/applymapping/sourcelibrary/InnerEnumValuesTest.java
index 4eb4585..aff0136 100644
--- a/src/test/java/com/android/tools/r8/naming/applymapping/sourcelibrary/InnerEnumValuesTest.java
+++ b/src/test/java/com/android/tools/r8/naming/applymapping/sourcelibrary/InnerEnumValuesTest.java
@@ -11,11 +11,11 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.applymapping.sourcelibrary.Outer.InnerEnum;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FieldSubject;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import org.junit.Before;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/naming/applymapping/sourcelibrary/MemberResolutionAsmTest.java b/src/test/java/com/android/tools/r8/naming/applymapping/sourcelibrary/MemberResolutionAsmTest.java
index e040cee..16be1d1 100644
--- a/src/test/java/com/android/tools/r8/naming/applymapping/sourcelibrary/MemberResolutionAsmTest.java
+++ b/src/test/java/com/android/tools/r8/naming/applymapping/sourcelibrary/MemberResolutionAsmTest.java
@@ -22,10 +22,10 @@
 import com.android.tools.r8.naming.applymapping.shared.SwappingDump.ADump;
 import com.android.tools.r8.naming.applymapping.shared.SwappingDump.BDump;
 import com.android.tools.r8.naming.applymapping.shared.SwappingDump.MainDump;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/naming/applymapping/sourcelibrary/MemberResolutionTest.java b/src/test/java/com/android/tools/r8/naming/applymapping/sourcelibrary/MemberResolutionTest.java
index 19dffa2..834c886 100644
--- a/src/test/java/com/android/tools/r8/naming/applymapping/sourcelibrary/MemberResolutionTest.java
+++ b/src/test/java/com/android/tools/r8/naming/applymapping/sourcelibrary/MemberResolutionTest.java
@@ -15,12 +15,12 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FieldSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Path;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/naming/applymapping/sourcelibrary/MultiDimensionalArrayTest.java b/src/test/java/com/android/tools/r8/naming/applymapping/sourcelibrary/MultiDimensionalArrayTest.java
index 771a820..9bae004 100644
--- a/src/test/java/com/android/tools/r8/naming/applymapping/sourcelibrary/MultiDimensionalArrayTest.java
+++ b/src/test/java/com/android/tools/r8/naming/applymapping/sourcelibrary/MultiDimensionalArrayTest.java
@@ -15,9 +15,9 @@
 import com.android.tools.r8.ToolHelper.ProcessResult;
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.utils.AndroidApp;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Path;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/naming/arraytypes/ArrayTypesTest.java b/src/test/java/com/android/tools/r8/naming/arraytypes/ArrayTypesTest.java
index fb4f3ef6..d2707e8 100644
--- a/src/test/java/com/android/tools/r8/naming/arraytypes/ArrayTypesTest.java
+++ b/src/test/java/com/android/tools/r8/naming/arraytypes/ArrayTypesTest.java
@@ -8,8 +8,8 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.lang.reflect.Method;
 import java.nio.file.Path;
 import java.util.function.Consumer;
diff --git a/src/test/java/com/android/tools/r8/naming/b114554345/B114554345.java b/src/test/java/com/android/tools/r8/naming/b114554345/B114554345.java
index c624ea7..c614e46 100644
--- a/src/test/java/com/android/tools/r8/naming/b114554345/B114554345.java
+++ b/src/test/java/com/android/tools/r8/naming/b114554345/B114554345.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.utils.InternalOptions.InlinerOptions;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/naming/b123068484/FieldRenamingTest.java b/src/test/java/com/android/tools/r8/naming/b123068484/FieldRenamingTest.java
index 65176e9..fbe4383 100644
--- a/src/test/java/com/android/tools/r8/naming/b123068484/FieldRenamingTest.java
+++ b/src/test/java/com/android/tools/r8/naming/b123068484/FieldRenamingTest.java
@@ -15,12 +15,12 @@
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.naming.b123068484.data.Concrete1;
 import com.android.tools.r8.naming.b123068484.runner.Runner;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FieldSubject;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Path;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/naming/b124357885/B124357885Test.java b/src/test/java/com/android/tools/r8/naming/b124357885/B124357885Test.java
index a77ff97..11a4a5c 100644
--- a/src/test/java/com/android/tools/r8/naming/b124357885/B124357885Test.java
+++ b/src/test/java/com/android/tools/r8/naming/b124357885/B124357885Test.java
@@ -17,11 +17,11 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.lang.reflect.Method;
 import java.lang.reflect.ParameterizedType;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/naming/b128656974/B128656974.java b/src/test/java/com/android/tools/r8/naming/b128656974/B128656974.java
index 24fd0b2..7757ab9 100644
--- a/src/test/java/com/android/tools/r8/naming/b128656974/B128656974.java
+++ b/src/test/java/com/android/tools/r8/naming/b128656974/B128656974.java
@@ -13,10 +13,10 @@
 import com.android.tools.r8.NoVerticalClassMerging;
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.naming.testclasses.Greeting;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.FieldSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 
 public class B128656974 extends TestBase {
diff --git a/src/test/java/com/android/tools/r8/naming/b130791310/B130791310.java b/src/test/java/com/android/tools/r8/naming/b130791310/B130791310.java
index 1467e33..bdaa077 100644
--- a/src/test/java/com/android/tools/r8/naming/b130791310/B130791310.java
+++ b/src/test/java/com/android/tools/r8/naming/b130791310/B130791310.java
@@ -12,12 +12,12 @@
 import com.android.tools.r8.ProguardVersion;
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.internal.BooleanUtils;
 import com.android.tools.r8.utils.InternalOptions.InlinerOptions;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/naming/b131810441/AnonymousClassRenamingTest.java b/src/test/java/com/android/tools/r8/naming/b131810441/AnonymousClassRenamingTest.java
index f77b662..b5da2e6 100644
--- a/src/test/java/com/android/tools/r8/naming/b131810441/AnonymousClassRenamingTest.java
+++ b/src/test/java/com/android/tools/r8/naming/b131810441/AnonymousClassRenamingTest.java
@@ -10,9 +10,9 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.naming.b131810441.sub.Outer;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Collection;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/naming/b132460884/LocalClassRenamingTest.java b/src/test/java/com/android/tools/r8/naming/b132460884/LocalClassRenamingTest.java
index e555c35..62294f7 100644
--- a/src/test/java/com/android/tools/r8/naming/b132460884/LocalClassRenamingTest.java
+++ b/src/test/java/com/android/tools/r8/naming/b132460884/LocalClassRenamingTest.java
@@ -9,9 +9,9 @@
 
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Collection;
 import java.util.HashMap;
 import java.util.HashSet;
diff --git a/src/test/java/com/android/tools/r8/naming/b133686361/AlreadyRenamedAbstractMethodRenamingTest.java b/src/test/java/com/android/tools/r8/naming/b133686361/AlreadyRenamedAbstractMethodRenamingTest.java
index 0e1dc72..318c9ad 100644
--- a/src/test/java/com/android/tools/r8/naming/b133686361/AlreadyRenamedAbstractMethodRenamingTest.java
+++ b/src/test/java/com/android/tools/r8/naming/b133686361/AlreadyRenamedAbstractMethodRenamingTest.java
@@ -13,10 +13,10 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/naming/b155249069/DontUseMixedCaseClassNamesExistingClassPackageTest.java b/src/test/java/com/android/tools/r8/naming/b155249069/DontUseMixedCaseClassNamesExistingClassPackageTest.java
index 3f1d4bd..a80247a 100644
--- a/src/test/java/com/android/tools/r8/naming/b155249069/DontUseMixedCaseClassNamesExistingClassPackageTest.java
+++ b/src/test/java/com/android/tools/r8/naming/b155249069/DontUseMixedCaseClassNamesExistingClassPackageTest.java
@@ -10,11 +10,11 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.naming.b155249069.package_b.A;
-import com.android.tools.r8.utils.internal.BooleanUtils;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.nio.file.Path;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/naming/b72391662/B72391662.java b/src/test/java/com/android/tools/r8/naming/b72391662/B72391662.java
index 1dd6409..d0d375b 100644
--- a/src/test/java/com/android/tools/r8/naming/b72391662/B72391662.java
+++ b/src/test/java/com/android/tools/r8/naming/b72391662/B72391662.java
@@ -18,10 +18,10 @@
 import com.android.tools.r8.naming.b72391662.subpackage.OtherPackageTestClass;
 import com.android.tools.r8.shaking.forceproguardcompatibility.ProguardCompatibilityTestBase;
 import com.android.tools.r8.utils.AndroidApp;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Iterables;
diff --git a/src/test/java/com/android/tools/r8/naming/identifiernamestring/IdentifierNameStringStaticFinalFieldTest.java b/src/test/java/com/android/tools/r8/naming/identifiernamestring/IdentifierNameStringStaticFinalFieldTest.java
index 6d0c21d..75910f3 100644
--- a/src/test/java/com/android/tools/r8/naming/identifiernamestring/IdentifierNameStringStaticFinalFieldTest.java
+++ b/src/test/java/com/android/tools/r8/naming/identifiernamestring/IdentifierNameStringStaticFinalFieldTest.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/naming/methodparameters/MethodParametersNullValueTest.java b/src/test/java/com/android/tools/r8/naming/methodparameters/MethodParametersNullValueTest.java
index e6a1197..f82d1d4 100644
--- a/src/test/java/com/android/tools/r8/naming/methodparameters/MethodParametersNullValueTest.java
+++ b/src/test/java/com/android/tools/r8/naming/methodparameters/MethodParametersNullValueTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.ToolHelper.DexVm.Version;
 import com.android.tools.r8.transformers.ClassFileTransformer.MethodPredicate;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.lang.reflect.MalformedParametersException;
 import java.lang.reflect.Method;
 import java.lang.reflect.Parameter;
diff --git a/src/test/java/com/android/tools/r8/naming/overloadaggressively/OverloadAggressivelyTest.java b/src/test/java/com/android/tools/r8/naming/overloadaggressively/OverloadAggressivelyTest.java
index 6ccaba2..d52e26a 100644
--- a/src/test/java/com/android/tools/r8/naming/overloadaggressively/OverloadAggressivelyTest.java
+++ b/src/test/java/com/android/tools/r8/naming/overloadaggressively/OverloadAggressivelyTest.java
@@ -18,9 +18,9 @@
 import com.android.tools.r8.graph.DexEncodedMethod;
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.utils.AndroidApp;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/naming/retrace/LineDeltaTest.java b/src/test/java/com/android/tools/r8/naming/retrace/LineDeltaTest.java
index de50d34..53cb70f 100644
--- a/src/test/java/com/android/tools/r8/naming/retrace/LineDeltaTest.java
+++ b/src/test/java/com/android/tools/r8/naming/retrace/LineDeltaTest.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/naming/retrace/StackTraceTest.java b/src/test/java/com/android/tools/r8/naming/retrace/StackTraceTest.java
index f866398..08f308b 100644
--- a/src/test/java/com/android/tools/r8/naming/retrace/StackTraceTest.java
+++ b/src/test/java/com/android/tools/r8/naming/retrace/StackTraceTest.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.naming.retrace.StackTrace.StackTraceLine;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/naming/retraceproguard/CatchAllRangeWithNoLineNumberTest.java b/src/test/java/com/android/tools/r8/naming/retraceproguard/CatchAllRangeWithNoLineNumberTest.java
index 6e42574..bf143bf 100644
--- a/src/test/java/com/android/tools/r8/naming/retraceproguard/CatchAllRangeWithNoLineNumberTest.java
+++ b/src/test/java/com/android/tools/r8/naming/retraceproguard/CatchAllRangeWithNoLineNumberTest.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.retrace.Retrace;
 import com.android.tools.r8.retrace.RetraceCommand;
 import com.android.tools.r8.utils.internal.Box;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.util.Arrays;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/naming/retraceproguard/LineDeltaTest.java b/src/test/java/com/android/tools/r8/naming/retraceproguard/LineDeltaTest.java
index 144b772..4ae5129 100644
--- a/src/test/java/com/android/tools/r8/naming/retraceproguard/LineDeltaTest.java
+++ b/src/test/java/com/android/tools/r8/naming/retraceproguard/LineDeltaTest.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/naming/retraceproguard/StackTrace.java b/src/test/java/com/android/tools/r8/naming/retraceproguard/StackTrace.java
index 6660a7d..4b9067e 100644
--- a/src/test/java/com/android/tools/r8/naming/retraceproguard/StackTrace.java
+++ b/src/test/java/com/android/tools/r8/naming/retraceproguard/StackTrace.java
@@ -13,8 +13,8 @@
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.ToolHelper.DexVm;
 import com.android.tools.r8.utils.internal.Box;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.base.Equivalence;
 import java.io.IOException;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/naming/retraceproguard/StackTraceTest.java b/src/test/java/com/android/tools/r8/naming/retraceproguard/StackTraceTest.java
index d1556fb..2e4244d 100644
--- a/src/test/java/com/android/tools/r8/naming/retraceproguard/StackTraceTest.java
+++ b/src/test/java/com/android/tools/r8/naming/retraceproguard/StackTraceTest.java
@@ -8,7 +8,7 @@
 import static org.junit.Assert.assertEquals;
 
 import com.android.tools.r8.naming.retraceproguard.StackTrace.StackTraceLine;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 
 public class StackTraceTest {
diff --git a/src/test/java/com/android/tools/r8/naming/sourcefile/StringPoolSizeWithLazyDexStringsTest.java b/src/test/java/com/android/tools/r8/naming/sourcefile/StringPoolSizeWithLazyDexStringsTest.java
index bfc8f65..c9f17bc 100644
--- a/src/test/java/com/android/tools/r8/naming/sourcefile/StringPoolSizeWithLazyDexStringsTest.java
+++ b/src/test/java/com/android/tools/r8/naming/sourcefile/StringPoolSizeWithLazyDexStringsTest.java
@@ -17,7 +17,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.dex.Constants;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Map;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/optimize/AnnotationImplementedAndInstantiatedInProgramTest.java b/src/test/java/com/android/tools/r8/optimize/AnnotationImplementedAndInstantiatedInProgramTest.java
index 83e0029..a6e930a 100644
--- a/src/test/java/com/android/tools/r8/optimize/AnnotationImplementedAndInstantiatedInProgramTest.java
+++ b/src/test/java/com/android/tools/r8/optimize/AnnotationImplementedAndInstantiatedInProgramTest.java
@@ -6,7 +6,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/optimize/argumentpropagation/UpwardsInterfacePropagationToLibraryOrClasspathMethodTest.java b/src/test/java/com/android/tools/r8/optimize/argumentpropagation/UpwardsInterfacePropagationToLibraryOrClasspathMethodTest.java
index e1b8630..278bf21 100644
--- a/src/test/java/com/android/tools/r8/optimize/argumentpropagation/UpwardsInterfacePropagationToLibraryOrClasspathMethodTest.java
+++ b/src/test/java/com/android/tools/r8/optimize/argumentpropagation/UpwardsInterfacePropagationToLibraryOrClasspathMethodTest.java
@@ -16,8 +16,8 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.HorizontallyMergedClassesInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/optimize/listiteration/B464035129Test.java b/src/test/java/com/android/tools/r8/optimize/listiteration/B464035129Test.java
index 7f694d8..69cc074 100644
--- a/src/test/java/com/android/tools/r8/optimize/listiteration/B464035129Test.java
+++ b/src/test/java/com/android/tools/r8/optimize/listiteration/B464035129Test.java
@@ -4,15 +4,15 @@
 package com.android.tools.r8.optimize.listiteration;
 
 import static com.android.tools.r8.utils.InternalOptions.ASM_VERSION;
-import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertTrue;
 
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.transformers.ClassTransformer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.ArrayList;
 import java.util.Iterator;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/optimize/numberconversion/ConversionTest.java b/src/test/java/com/android/tools/r8/optimize/numberconversion/ConversionTest.java
index 2f5af4d..d25e8c9 100644
--- a/src/test/java/com/android/tools/r8/optimize/numberconversion/ConversionTest.java
+++ b/src/test/java/com/android/tools/r8/optimize/numberconversion/ConversionTest.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/optimize/serviceloader/MissingServiceClassTest.java b/src/test/java/com/android/tools/r8/optimize/serviceloader/MissingServiceClassTest.java
index be9a7ea..235871d 100644
--- a/src/test/java/com/android/tools/r8/optimize/serviceloader/MissingServiceClassTest.java
+++ b/src/test/java/com/android/tools/r8/optimize/serviceloader/MissingServiceClassTest.java
@@ -18,7 +18,7 @@
 import com.android.tools.r8.graph.AppServices;
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.utils.DataResourceConsumerForTesting;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import java.util.ServiceLoader;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/optimize/serviceloader/MissingServiceClassWithFeatureTest.java b/src/test/java/com/android/tools/r8/optimize/serviceloader/MissingServiceClassWithFeatureTest.java
index 02f30ad..3f729ee 100644
--- a/src/test/java/com/android/tools/r8/optimize/serviceloader/MissingServiceClassWithFeatureTest.java
+++ b/src/test/java/com/android/tools/r8/optimize/serviceloader/MissingServiceClassWithFeatureTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.graph.AppServices;
 import com.android.tools.r8.origin.Origin;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.ServiceLoader;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/optimize/serviceloader/MissingServiceImplementationClassTest.java b/src/test/java/com/android/tools/r8/optimize/serviceloader/MissingServiceImplementationClassTest.java
index fe0e84a..5bf7b56 100644
--- a/src/test/java/com/android/tools/r8/optimize/serviceloader/MissingServiceImplementationClassTest.java
+++ b/src/test/java/com/android/tools/r8/optimize/serviceloader/MissingServiceImplementationClassTest.java
@@ -16,11 +16,11 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.graph.AppServices;
 import com.android.tools.r8.origin.Origin;
-import com.android.tools.r8.utils.internal.Box;
 import com.android.tools.r8.utils.DataResourceConsumerForTesting;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.Box;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.io.ByteStreams;
 import java.nio.file.Files;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/optimize/serviceloader/MissingServiceImplementationClassWithFeatureTest.java b/src/test/java/com/android/tools/r8/optimize/serviceloader/MissingServiceImplementationClassWithFeatureTest.java
index 9401a7d..0b240ad 100644
--- a/src/test/java/com/android/tools/r8/optimize/serviceloader/MissingServiceImplementationClassWithFeatureTest.java
+++ b/src/test/java/com/android/tools/r8/optimize/serviceloader/MissingServiceImplementationClassWithFeatureTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.graph.AppServices;
 import com.android.tools.r8.origin.Origin;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.ServiceLoader;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/optimize/serviceloader/ServiceLoaderClassLoaderRewritingTest.java b/src/test/java/com/android/tools/r8/optimize/serviceloader/ServiceLoaderClassLoaderRewritingTest.java
index 9695e90..f601907 100644
--- a/src/test/java/com/android/tools/r8/optimize/serviceloader/ServiceLoaderClassLoaderRewritingTest.java
+++ b/src/test/java/com/android/tools/r8/optimize/serviceloader/ServiceLoaderClassLoaderRewritingTest.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.NeverInline;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.ServiceLoader;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/optimize/serviceloader/ServiceLoaderDesugaredLibraryTest.java b/src/test/java/com/android/tools/r8/optimize/serviceloader/ServiceLoaderDesugaredLibraryTest.java
index 98a66a3..0d1ed95 100644
--- a/src/test/java/com/android/tools/r8/optimize/serviceloader/ServiceLoaderDesugaredLibraryTest.java
+++ b/src/test/java/com/android/tools/r8/optimize/serviceloader/ServiceLoaderDesugaredLibraryTest.java
@@ -19,8 +19,8 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.origin.Origin;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.ZipUtils.ZipBuilder;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.io.Serializable;
diff --git a/src/test/java/com/android/tools/r8/optimize/serviceloader/ServiceLoaderMultipleCallsSameMethodTest.java b/src/test/java/com/android/tools/r8/optimize/serviceloader/ServiceLoaderMultipleCallsSameMethodTest.java
index 5cd038d..10aa8a4c 100644
--- a/src/test/java/com/android/tools/r8/optimize/serviceloader/ServiceLoaderMultipleCallsSameMethodTest.java
+++ b/src/test/java/com/android/tools/r8/optimize/serviceloader/ServiceLoaderMultipleCallsSameMethodTest.java
@@ -12,8 +12,8 @@
 import com.android.tools.r8.NeverInline;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.FoundClassSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.util.ServiceLoader;
 import java.util.concurrent.ExecutionException;
diff --git a/src/test/java/com/android/tools/r8/optimize/serviceloader/ServiceLoaderMultipleCallsTest.java b/src/test/java/com/android/tools/r8/optimize/serviceloader/ServiceLoaderMultipleCallsTest.java
index 5b2d452..12c975e 100644
--- a/src/test/java/com/android/tools/r8/optimize/serviceloader/ServiceLoaderMultipleCallsTest.java
+++ b/src/test/java/com/android/tools/r8/optimize/serviceloader/ServiceLoaderMultipleCallsTest.java
@@ -12,8 +12,8 @@
 import com.android.tools.r8.NeverInline;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.FoundClassSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.util.ServiceLoader;
 import java.util.concurrent.ExecutionException;
diff --git a/src/test/java/com/android/tools/r8/optimize/serviceloader/ServiceLoaderMultipleTest.java b/src/test/java/com/android/tools/r8/optimize/serviceloader/ServiceLoaderMultipleTest.java
index 99165f5..3bff6bb 100644
--- a/src/test/java/com/android/tools/r8/optimize/serviceloader/ServiceLoaderMultipleTest.java
+++ b/src/test/java/com/android/tools/r8/optimize/serviceloader/ServiceLoaderMultipleTest.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.ServiceLoader;
 import org.junit.BeforeClass;
diff --git a/src/test/java/com/android/tools/r8/optimize/serviceloader/ServiceLoaderRewritingLineSeparatorTest.java b/src/test/java/com/android/tools/r8/optimize/serviceloader/ServiceLoaderRewritingLineSeparatorTest.java
index 0e39082..eab2388 100644
--- a/src/test/java/com/android/tools/r8/optimize/serviceloader/ServiceLoaderRewritingLineSeparatorTest.java
+++ b/src/test/java/com/android/tools/r8/optimize/serviceloader/ServiceLoaderRewritingLineSeparatorTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.DataEntryResource;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.origin.Origin;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.util.List;
 import java.util.concurrent.ExecutionException;
diff --git a/src/test/java/com/android/tools/r8/optimize/serviceloader/ServiceLoaderRewritingTest.java b/src/test/java/com/android/tools/r8/optimize/serviceloader/ServiceLoaderRewritingTest.java
index 74fe09c..367ec89 100644
--- a/src/test/java/com/android/tools/r8/optimize/serviceloader/ServiceLoaderRewritingTest.java
+++ b/src/test/java/com/android/tools/r8/optimize/serviceloader/ServiceLoaderRewritingTest.java
@@ -11,9 +11,9 @@
 import com.android.tools.r8.CompilationFailedException;
 import com.android.tools.r8.NeverInline;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.util.List;
 import java.util.NoSuchElementException;
diff --git a/src/test/java/com/android/tools/r8/optimize/serviceloader/ServiceLoaderRewritingWithAssumeNoSideEffectsTest.java b/src/test/java/com/android/tools/r8/optimize/serviceloader/ServiceLoaderRewritingWithAssumeNoSideEffectsTest.java
index 4de5ec7..ad9f8aa 100644
--- a/src/test/java/com/android/tools/r8/optimize/serviceloader/ServiceLoaderRewritingWithAssumeNoSideEffectsTest.java
+++ b/src/test/java/com/android/tools/r8/optimize/serviceloader/ServiceLoaderRewritingWithAssumeNoSideEffectsTest.java
@@ -10,8 +10,8 @@
 import com.android.tools.r8.R8FullTestBuilder;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.util.Iterator;
 import java.util.ServiceLoader;
diff --git a/src/test/java/com/android/tools/r8/optimize/serviceloader/ServiceLoaderTest.java b/src/test/java/com/android/tools/r8/optimize/serviceloader/ServiceLoaderTest.java
index c270671..fd6eaba 100644
--- a/src/test/java/com/android/tools/r8/optimize/serviceloader/ServiceLoaderTest.java
+++ b/src/test/java/com/android/tools/r8/optimize/serviceloader/ServiceLoaderTest.java
@@ -23,13 +23,13 @@
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.references.ClassReference;
 import com.android.tools.r8.references.MethodReference;
-import com.android.tools.r8.utils.internal.BooleanUtils;
 import com.android.tools.r8.utils.DataResourceConsumerForTesting;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.graphinspector.GraphInspector;
 import com.android.tools.r8.utils.graphinspector.GraphInspector.QueryNode;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.Lists;
 import java.util.List;
 import java.util.ServiceLoader;
diff --git a/src/test/java/com/android/tools/r8/optimize/serviceloader/VerticalClassMergingServiceLoaderTest.java b/src/test/java/com/android/tools/r8/optimize/serviceloader/VerticalClassMergingServiceLoaderTest.java
index 6b6008f..0f5ad3a 100644
--- a/src/test/java/com/android/tools/r8/optimize/serviceloader/VerticalClassMergingServiceLoaderTest.java
+++ b/src/test/java/com/android/tools/r8/optimize/serviceloader/VerticalClassMergingServiceLoaderTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.origin.Origin;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.Lists;
 import java.io.IOException;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/partial/PartialCompilationCalledByNativeTest.java b/src/test/java/com/android/tools/r8/partial/PartialCompilationCalledByNativeTest.java
index 834ccd6..287133d 100644
--- a/src/test/java/com/android/tools/r8/partial/PartialCompilationCalledByNativeTest.java
+++ b/src/test/java/com/android/tools/r8/partial/PartialCompilationCalledByNativeTest.java
@@ -11,10 +11,10 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/partial/PartialCompilationClassAnnotatedInD8Test.java b/src/test/java/com/android/tools/r8/partial/PartialCompilationClassAnnotatedInD8Test.java
index 9edf674..8dfe569 100644
--- a/src/test/java/com/android/tools/r8/partial/PartialCompilationClassAnnotatedInD8Test.java
+++ b/src/test/java/com/android/tools/r8/partial/PartialCompilationClassAnnotatedInD8Test.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/partial/PartialCompilationDemoTest.java b/src/test/java/com/android/tools/r8/partial/PartialCompilationDemoTest.java
index cb94808..1da1660 100644
--- a/src/test/java/com/android/tools/r8/partial/PartialCompilationDemoTest.java
+++ b/src/test/java/com/android/tools/r8/partial/PartialCompilationDemoTest.java
@@ -25,9 +25,9 @@
 import com.android.tools.r8.tracereferences.TraceReferencesCommand;
 import com.android.tools.r8.tracereferences.TraceReferencesKeepRules;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.internal.Box;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.ZipUtils;
+import com.android.tools.r8.utils.internal.Box;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.android.tools.r8.utils.internal.collections.Pair;
 import com.google.common.collect.ImmutableMap;
 import java.io.IOException;
diff --git a/src/test/java/com/android/tools/r8/partial/PartialCompilationFieldAnnotatedInD8Test.java b/src/test/java/com/android/tools/r8/partial/PartialCompilationFieldAnnotatedInD8Test.java
index 61e7766..d9c1244 100644
--- a/src/test/java/com/android/tools/r8/partial/PartialCompilationFieldAnnotatedInD8Test.java
+++ b/src/test/java/com/android/tools/r8/partial/PartialCompilationFieldAnnotatedInD8Test.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/partial/PartialCompilationIdentifierNameStringFieldTest.java b/src/test/java/com/android/tools/r8/partial/PartialCompilationIdentifierNameStringFieldTest.java
index 16ab318..1d005cf 100644
--- a/src/test/java/com/android/tools/r8/partial/PartialCompilationIdentifierNameStringFieldTest.java
+++ b/src/test/java/com/android/tools/r8/partial/PartialCompilationIdentifierNameStringFieldTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/partial/PartialCompilationIdentifierNameStringMethodTest.java b/src/test/java/com/android/tools/r8/partial/PartialCompilationIdentifierNameStringMethodTest.java
index d69b5e0..890875f 100644
--- a/src/test/java/com/android/tools/r8/partial/PartialCompilationIdentifierNameStringMethodTest.java
+++ b/src/test/java/com/android/tools/r8/partial/PartialCompilationIdentifierNameStringMethodTest.java
@@ -6,7 +6,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/partial/PartialCompilationIncludeDescriptorClassesTest.java b/src/test/java/com/android/tools/r8/partial/PartialCompilationIncludeDescriptorClassesTest.java
index 34a28f5..d9b0792 100644
--- a/src/test/java/com/android/tools/r8/partial/PartialCompilationIncludeDescriptorClassesTest.java
+++ b/src/test/java/com/android/tools/r8/partial/PartialCompilationIncludeDescriptorClassesTest.java
@@ -11,10 +11,10 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/partial/PartialCompilationMethodAnnotatedInD8Test.java b/src/test/java/com/android/tools/r8/partial/PartialCompilationMethodAnnotatedInD8Test.java
index 2ae767a..1c398ea 100644
--- a/src/test/java/com/android/tools/r8/partial/PartialCompilationMethodAnnotatedInD8Test.java
+++ b/src/test/java/com/android/tools/r8/partial/PartialCompilationMethodAnnotatedInD8Test.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/partial/PartialCompilationPrintConfigurationTest.java b/src/test/java/com/android/tools/r8/partial/PartialCompilationPrintConfigurationTest.java
index 45276b3..77e64bf 100644
--- a/src/test/java/com/android/tools/r8/partial/PartialCompilationPrintConfigurationTest.java
+++ b/src/test/java/com/android/tools/r8/partial/PartialCompilationPrintConfigurationTest.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/partial/PartialCompilationSynchronizedMethodExcludedTest.java b/src/test/java/com/android/tools/r8/partial/PartialCompilationSynchronizedMethodExcludedTest.java
index ebbd0f0..8ff3ffe 100644
--- a/src/test/java/com/android/tools/r8/partial/PartialCompilationSynchronizedMethodExcludedTest.java
+++ b/src/test/java/com/android/tools/r8/partial/PartialCompilationSynchronizedMethodExcludedTest.java
@@ -8,8 +8,8 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/partial/PartialCompilationSynchronizedMethodIncludedTest.java b/src/test/java/com/android/tools/r8/partial/PartialCompilationSynchronizedMethodIncludedTest.java
index e3404b7..6b13d8d 100644
--- a/src/test/java/com/android/tools/r8/partial/PartialCompilationSynchronizedMethodIncludedTest.java
+++ b/src/test/java/com/android/tools/r8/partial/PartialCompilationSynchronizedMethodIncludedTest.java
@@ -8,8 +8,8 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/partial/PartialCompilationWhyAreYouKeepingFromExcludedClassTest.java b/src/test/java/com/android/tools/r8/partial/PartialCompilationWhyAreYouKeepingFromExcludedClassTest.java
index 611df5c..7a11162 100644
--- a/src/test/java/com/android/tools/r8/partial/PartialCompilationWhyAreYouKeepingFromExcludedClassTest.java
+++ b/src/test/java/com/android/tools/r8/partial/PartialCompilationWhyAreYouKeepingFromExcludedClassTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.utils.MethodReferenceUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/partial/kotlin/PartialCompilationKotlinMetadataTest.java b/src/test/java/com/android/tools/r8/partial/kotlin/PartialCompilationKotlinMetadataTest.java
index 6856824..f5bcb44 100644
--- a/src/test/java/com/android/tools/r8/partial/kotlin/PartialCompilationKotlinMetadataTest.java
+++ b/src/test/java/com/android/tools/r8/partial/kotlin/PartialCompilationKotlinMetadataTest.java
@@ -15,11 +15,11 @@
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.kotlin.KotlinMetadataWriter;
 import com.android.tools.r8.kotlin.metadata.KotlinMetadataTestBase;
-import com.android.tools.r8.utils.internal.BooleanUtils;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import java.nio.file.Paths;
 import java.util.List;
 import kotlin.metadata.jvm.KotlinClassMetadata;
diff --git a/src/test/java/com/android/tools/r8/peephole/suffixsharing/IdenticalBlockSuffixSharingWithArrayTypesTest.java b/src/test/java/com/android/tools/r8/peephole/suffixsharing/IdenticalBlockSuffixSharingWithArrayTypesTest.java
index 5a531a5..9b95aeb 100644
--- a/src/test/java/com/android/tools/r8/peephole/suffixsharing/IdenticalBlockSuffixSharingWithArrayTypesTest.java
+++ b/src/test/java/com/android/tools/r8/peephole/suffixsharing/IdenticalBlockSuffixSharingWithArrayTypesTest.java
@@ -15,11 +15,11 @@
 import com.android.tools.r8.NoHorizontalClassMerging;
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/processkeeprules/ProcessKeepRulesFilteringTest.java b/src/test/java/com/android/tools/r8/processkeeprules/ProcessKeepRulesFilteringTest.java
index bd1cde6..6a9c1e8 100644
--- a/src/test/java/com/android/tools/r8/processkeeprules/ProcessKeepRulesFilteringTest.java
+++ b/src/test/java/com/android/tools/r8/processkeeprules/ProcessKeepRulesFilteringTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.origin.Origin;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/processkeeprules/sanitychecks/ProcessKeepRulesSanityCheckTest.java b/src/test/java/com/android/tools/r8/processkeeprules/sanitychecks/ProcessKeepRulesSanityCheckTest.java
index bd4e06f..6161e82 100644
--- a/src/test/java/com/android/tools/r8/processkeeprules/sanitychecks/ProcessKeepRulesSanityCheckTest.java
+++ b/src/test/java/com/android/tools/r8/processkeeprules/sanitychecks/ProcessKeepRulesSanityCheckTest.java
@@ -16,10 +16,10 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.Version;
-import com.android.tools.r8.utils.internal.BooleanBox;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.internal.StreamUtils;
 import com.android.tools.r8.utils.ZipUtils;
+import com.android.tools.r8.utils.internal.BooleanBox;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StreamUtils;
 import java.nio.file.Files;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/profile/art/dump/DumpArtProfileProvidersTest.java b/src/test/java/com/android/tools/r8/profile/art/dump/DumpArtProfileProvidersTest.java
index 83f869c..10028cf 100644
--- a/src/test/java/com/android/tools/r8/profile/art/dump/DumpArtProfileProvidersTest.java
+++ b/src/test/java/com/android/tools/r8/profile/art/dump/DumpArtProfileProvidersTest.java
@@ -25,11 +25,11 @@
 import com.android.tools.r8.references.MethodReference;
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.utils.DumpInputFlags;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.MethodReferenceUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.UTF8TextInputStream;
 import com.android.tools.r8.utils.ZipUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Lists;
 import java.io.IOException;
diff --git a/src/test/java/com/android/tools/r8/profile/art/format/ArtProfileWithCommentsAndWhitespaceTest.java b/src/test/java/com/android/tools/r8/profile/art/format/ArtProfileWithCommentsAndWhitespaceTest.java
index 77ffaf9..66ab95f 100644
--- a/src/test/java/com/android/tools/r8/profile/art/format/ArtProfileWithCommentsAndWhitespaceTest.java
+++ b/src/test/java/com/android/tools/r8/profile/art/format/ArtProfileWithCommentsAndWhitespaceTest.java
@@ -14,9 +14,9 @@
 import com.android.tools.r8.profile.art.ArtProfileProvider;
 import com.android.tools.r8.profile.art.utils.ArtProfileInspector;
 import com.android.tools.r8.references.MethodReference;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.MethodReferenceUtils;
 import com.android.tools.r8.utils.UTF8TextInputStream;
+import com.android.tools.r8.utils.internal.FileUtils;
 import java.io.IOException;
 import java.io.UncheckedIOException;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/profile/art/format/ArtProfileWithFlagsInAnyOrderTest.java b/src/test/java/com/android/tools/r8/profile/art/format/ArtProfileWithFlagsInAnyOrderTest.java
index f4a074d..702d632 100644
--- a/src/test/java/com/android/tools/r8/profile/art/format/ArtProfileWithFlagsInAnyOrderTest.java
+++ b/src/test/java/com/android/tools/r8/profile/art/format/ArtProfileWithFlagsInAnyOrderTest.java
@@ -20,9 +20,9 @@
 import com.android.tools.r8.profile.art.diagnostic.HumanReadableArtProfileParserErrorDiagnostic;
 import com.android.tools.r8.profile.art.utils.ArtProfileInspector;
 import com.android.tools.r8.references.MethodReference;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.MethodReferenceUtils;
 import com.android.tools.r8.utils.UTF8TextInputStream;
+import com.android.tools.r8.utils.internal.FileUtils;
 import java.io.IOException;
 import java.io.UncheckedIOException;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/profile/art/format/ArtProfileWithWildcardsTest.java b/src/test/java/com/android/tools/r8/profile/art/format/ArtProfileWithWildcardsTest.java
index 93a6e17..4cf8b3d 100644
--- a/src/test/java/com/android/tools/r8/profile/art/format/ArtProfileWithWildcardsTest.java
+++ b/src/test/java/com/android/tools/r8/profile/art/format/ArtProfileWithWildcardsTest.java
@@ -20,9 +20,9 @@
 import com.android.tools.r8.profile.art.diagnostic.HumanReadableArtProfileParserErrorDiagnostic;
 import com.android.tools.r8.profile.art.utils.ArtProfileInspector;
 import com.android.tools.r8.references.Reference;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.UTF8TextInputStream;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.io.UncheckedIOException;
diff --git a/src/test/java/com/android/tools/r8/proguard/NonExistingConfigFileTest.java b/src/test/java/com/android/tools/r8/proguard/NonExistingConfigFileTest.java
index b241eff..b82f523 100644
--- a/src/test/java/com/android/tools/r8/proguard/NonExistingConfigFileTest.java
+++ b/src/test/java/com/android/tools/r8/proguard/NonExistingConfigFileTest.java
@@ -10,8 +10,8 @@
 
 import com.android.tools.r8.CompilationFailedException;
 import com.android.tools.r8.TestBase;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
+import com.android.tools.r8.utils.internal.FileUtils;
 import java.nio.file.Path;
 import org.junit.Test;
 
@@ -49,4 +49,4 @@
   }
 
   static class TestClass {}
-}
\ No newline at end of file
+}
diff --git a/src/test/java/com/android/tools/r8/proguard/configuration/ProguardRuleWithEllipsisForReturnTypeTest.java b/src/test/java/com/android/tools/r8/proguard/configuration/ProguardRuleWithEllipsisForReturnTypeTest.java
index c7091c2..10f4210 100644
--- a/src/test/java/com/android/tools/r8/proguard/configuration/ProguardRuleWithEllipsisForReturnTypeTest.java
+++ b/src/test/java/com/android/tools/r8/proguard/configuration/ProguardRuleWithEllipsisForReturnTypeTest.java
@@ -11,9 +11,9 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/proguard/configuration/RepackagingCompatibilityTest.java b/src/test/java/com/android/tools/r8/proguard/configuration/RepackagingCompatibilityTest.java
index 89e1757..7e2b4e0 100644
--- a/src/test/java/com/android/tools/r8/proguard/configuration/RepackagingCompatibilityTest.java
+++ b/src/test/java/com/android/tools/r8/proguard/configuration/RepackagingCompatibilityTest.java
@@ -14,9 +14,9 @@
 
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestShrinkerBuilder;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/proguard/rules/NegatedClassMemberTest.java b/src/test/java/com/android/tools/r8/proguard/rules/NegatedClassMemberTest.java
index bdd9eb8..e362e40 100644
--- a/src/test/java/com/android/tools/r8/proguard/rules/NegatedClassMemberTest.java
+++ b/src/test/java/com/android/tools/r8/proguard/rules/NegatedClassMemberTest.java
@@ -15,7 +15,7 @@
 import com.android.tools.r8.TestDiagnosticMessages;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/reachabilitysensitive/ReachabilitySensitiveAndDebugLocalReads.java b/src/test/java/com/android/tools/r8/reachabilitysensitive/ReachabilitySensitiveAndDebugLocalReads.java
index 4d0d3e6..2fd7475 100644
--- a/src/test/java/com/android/tools/r8/reachabilitysensitive/ReachabilitySensitiveAndDebugLocalReads.java
+++ b/src/test/java/com/android/tools/r8/reachabilitysensitive/ReachabilitySensitiveAndDebugLocalReads.java
@@ -6,7 +6,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.BeforeClass;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/regress/B341618078Test.java b/src/test/java/com/android/tools/r8/regress/B341618078Test.java
index dee949e..65bf44b 100644
--- a/src/test/java/com/android/tools/r8/regress/B341618078Test.java
+++ b/src/test/java/com/android/tools/r8/regress/B341618078Test.java
@@ -9,8 +9,8 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/regress/Regress120894450.java b/src/test/java/com/android/tools/r8/regress/Regress120894450.java
index 5c36107..6710590 100644
--- a/src/test/java/com/android/tools/r8/regress/Regress120894450.java
+++ b/src/test/java/com/android/tools/r8/regress/Regress120894450.java
@@ -6,7 +6,7 @@
 
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.naming.ClassNameMapper;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 
 public class Regress120894450 extends TestBase {
diff --git a/src/test/java/com/android/tools/r8/regress/Regress160394262Test.java b/src/test/java/com/android/tools/r8/regress/Regress160394262Test.java
index e21af03..169d0fb 100644
--- a/src/test/java/com/android/tools/r8/regress/Regress160394262Test.java
+++ b/src/test/java/com/android/tools/r8/regress/Regress160394262Test.java
@@ -9,8 +9,8 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.util.Arrays;
 import java.util.Iterator;
diff --git a/src/test/java/com/android/tools/r8/regress/Regress160831625Test.java b/src/test/java/com/android/tools/r8/regress/Regress160831625Test.java
index f2b9b91..05a7a81 100644
--- a/src/test/java/com/android/tools/r8/regress/Regress160831625Test.java
+++ b/src/test/java/com/android/tools/r8/regress/Regress160831625Test.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/regress/UndefinedLambdaInterfaceRegress232379893.java b/src/test/java/com/android/tools/r8/regress/UndefinedLambdaInterfaceRegress232379893.java
index bf90e3a..11dfc39 100644
--- a/src/test/java/com/android/tools/r8/regress/UndefinedLambdaInterfaceRegress232379893.java
+++ b/src/test/java/com/android/tools/r8/regress/UndefinedLambdaInterfaceRegress232379893.java
@@ -11,8 +11,8 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.UnverifiableCfCodeDiagnostic;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/regress/b118075510/Regress118075510Runner.java b/src/test/java/com/android/tools/r8/regress/b118075510/Regress118075510Runner.java
index 2345ec3..6175fa8 100644
--- a/src/test/java/com/android/tools/r8/regress/b118075510/Regress118075510Runner.java
+++ b/src/test/java/com/android/tools/r8/regress/b118075510/Regress118075510Runner.java
@@ -8,9 +8,9 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Assert;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/regress/b122887884/Regress122887884Runner.java b/src/test/java/com/android/tools/r8/regress/b122887884/Regress122887884Runner.java
index 54f32fd..8acf7f8 100644
--- a/src/test/java/com/android/tools/r8/regress/b122887884/Regress122887884Runner.java
+++ b/src/test/java/com/android/tools/r8/regress/b122887884/Regress122887884Runner.java
@@ -4,7 +4,7 @@
 package com.android.tools.r8.regress.b122887884;
 
 import com.android.tools.r8.TestBase;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 
 public class Regress122887884Runner extends TestBase {
diff --git a/src/test/java/com/android/tools/r8/regress/b149890887/MissingLibraryTargetTest.java b/src/test/java/com/android/tools/r8/regress/b149890887/MissingLibraryTargetTest.java
index 7648d6d53..cedd60d 100644
--- a/src/test/java/com/android/tools/r8/regress/b149890887/MissingLibraryTargetTest.java
+++ b/src/test/java/com/android/tools/r8/regress/b149890887/MissingLibraryTargetTest.java
@@ -6,7 +6,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Path;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/regress/b150688800/IdempotentCountErrorTest.java b/src/test/java/com/android/tools/r8/regress/b150688800/IdempotentCountErrorTest.java
index 6742fda..1e097c3 100644
--- a/src/test/java/com/android/tools/r8/regress/b150688800/IdempotentCountErrorTest.java
+++ b/src/test/java/com/android/tools/r8/regress/b150688800/IdempotentCountErrorTest.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/regress/b152800551/StaticizerGetterRewritingRegressionTest.java b/src/test/java/com/android/tools/r8/regress/b152800551/StaticizerGetterRewritingRegressionTest.java
index 48ab187..8536f9b 100644
--- a/src/test/java/com/android/tools/r8/regress/b152800551/StaticizerGetterRewritingRegressionTest.java
+++ b/src/test/java/com/android/tools/r8/regress/b152800551/StaticizerGetterRewritingRegressionTest.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/regress/b163264839/Regress163264839Test.java b/src/test/java/com/android/tools/r8/regress/b163264839/Regress163264839Test.java
index 83e9eec..d841fcd 100644
--- a/src/test/java/com/android/tools/r8/regress/b163264839/Regress163264839Test.java
+++ b/src/test/java/com/android/tools/r8/regress/b163264839/Regress163264839Test.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.transformers.MethodTransformer;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/regress/b165825758/Regress165825758Test.java b/src/test/java/com/android/tools/r8/regress/b165825758/Regress165825758Test.java
index 4034d59..aeb60c8 100644
--- a/src/test/java/com/android/tools/r8/regress/b165825758/Regress165825758Test.java
+++ b/src/test/java/com/android/tools/r8/regress/b165825758/Regress165825758Test.java
@@ -13,7 +13,6 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionOffsetSubject;
@@ -21,6 +20,7 @@
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
 import com.android.tools.r8.utils.codeinspector.RangeSubject;
 import com.android.tools.r8.utils.codeinspector.TryCatchSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import java.util.stream.Collectors;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/regress/b316744331/Regress316744331Test.java b/src/test/java/com/android/tools/r8/regress/b316744331/Regress316744331Test.java
index 2bcf2f7..b78fa17 100644
--- a/src/test/java/com/android/tools/r8/regress/b316744331/Regress316744331Test.java
+++ b/src/test/java/com/android/tools/r8/regress/b316744331/Regress316744331Test.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.debug.DebugTestBase;
 import com.android.tools.r8.references.MethodReference;
 import com.android.tools.r8.references.Reference;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.apache.harmony.jpda.tests.framework.jdwp.JDWPConstants.Tag;
 import org.apache.harmony.jpda.tests.framework.jdwp.Value;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/regress/b426351560/Regress426351560Test.java b/src/test/java/com/android/tools/r8/regress/b426351560/Regress426351560Test.java
index c11e2a0..99e7acf 100644
--- a/src/test/java/com/android/tools/r8/regress/b426351560/Regress426351560Test.java
+++ b/src/test/java/com/android/tools/r8/regress/b426351560/Regress426351560Test.java
@@ -3,13 +3,12 @@
 // BSD-style license that can be found in the LICENSE file.
 package com.android.tools.r8.regress.b426351560;
 
-import static org.junit.Assume.assumeFalse;
 
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.regress.b426351560.testclasses.Regress426351560TestClasses;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/regress/b76025099/B76025099.java b/src/test/java/com/android/tools/r8/regress/b76025099/B76025099.java
index e0b1d4f..6978af8 100644
--- a/src/test/java/com/android/tools/r8/regress/b76025099/B76025099.java
+++ b/src/test/java/com/android/tools/r8/regress/b76025099/B76025099.java
@@ -17,12 +17,12 @@
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.regress.b76025099.testclasses.Main;
 import com.android.tools.r8.regress.b76025099.testclasses.impl.Impl;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FieldAccessInstructionSubject;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Iterator;
 import java.util.function.Function;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/regress/b78493232/Regress78493232_WithPhi.java b/src/test/java/com/android/tools/r8/regress/b78493232/Regress78493232_WithPhi.java
index 07b52af..e4656b2 100644
--- a/src/test/java/com/android/tools/r8/regress/b78493232/Regress78493232_WithPhi.java
+++ b/src/test/java/com/android/tools/r8/regress/b78493232/Regress78493232_WithPhi.java
@@ -15,7 +15,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRunResult;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/relocator/RelocatorServiceLoaderTest.java b/src/test/java/com/android/tools/r8/relocator/RelocatorServiceLoaderTest.java
index 7bbe066..447db67 100644
--- a/src/test/java/com/android/tools/r8/relocator/RelocatorServiceLoaderTest.java
+++ b/src/test/java/com/android/tools/r8/relocator/RelocatorServiceLoaderTest.java
@@ -16,8 +16,8 @@
 import com.android.tools.r8.relocator.foo.bar.Baz;
 import com.android.tools.r8.relocator.foo.bar.BazImpl;
 import com.android.tools.r8.relocator.foo.baz.OtherImpl;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.ZipUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.File;
 import java.io.IOException;
 import java.io.InputStream;
diff --git a/src/test/java/com/android/tools/r8/repackage/MappingFileAfterRepackagingTest.java b/src/test/java/com/android/tools/r8/repackage/MappingFileAfterRepackagingTest.java
index 554d19a..8ca04e2 100644
--- a/src/test/java/com/android/tools/r8/repackage/MappingFileAfterRepackagingTest.java
+++ b/src/test/java/com/android/tools/r8/repackage/MappingFileAfterRepackagingTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestShrinkerBuilder;
 import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/repackage/RepackageFeatureWithSyntheticsTest.java b/src/test/java/com/android/tools/r8/repackage/RepackageFeatureWithSyntheticsTest.java
index 59f4dc4..3b6d958 100644
--- a/src/test/java/com/android/tools/r8/repackage/RepackageFeatureWithSyntheticsTest.java
+++ b/src/test/java/com/android/tools/r8/repackage/RepackageFeatureWithSyntheticsTest.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.R8TestCompileResult;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.references.Reference;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/repackage/RepackageTestBase.java b/src/test/java/com/android/tools/r8/repackage/RepackageTestBase.java
index 2fbc260..b2afbe9 100644
--- a/src/test/java/com/android/tools/r8/repackage/RepackageTestBase.java
+++ b/src/test/java/com/android/tools/r8/repackage/RepackageTestBase.java
@@ -10,9 +10,9 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestShrinkerBuilder;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.ArrayList;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/repackage/RepackageWithServiceLoaderTest.java b/src/test/java/com/android/tools/r8/repackage/RepackageWithServiceLoaderTest.java
index 55f8bed..31ca797 100644
--- a/src/test/java/com/android/tools/r8/repackage/RepackageWithServiceLoaderTest.java
+++ b/src/test/java/com/android/tools/r8/repackage/RepackageWithServiceLoaderTest.java
@@ -14,12 +14,12 @@
 import com.android.tools.r8.R8TestRunResult;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.origin.Origin;
-import com.android.tools.r8.utils.internal.Box;
 import com.android.tools.r8.utils.DataResourceConsumerForTesting;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
+import com.android.tools.r8.utils.internal.Box;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import java.util.ServiceLoader;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/resolution/LibraryExtendsProgramRefinedReceiverIsLibraryClass.java b/src/test/java/com/android/tools/r8/resolution/LibraryExtendsProgramRefinedReceiverIsLibraryClass.java
index c5aafe9..83015fe 100644
--- a/src/test/java/com/android/tools/r8/resolution/LibraryExtendsProgramRefinedReceiverIsLibraryClass.java
+++ b/src/test/java/com/android/tools/r8/resolution/LibraryExtendsProgramRefinedReceiverIsLibraryClass.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/resolution/PublicFieldInnerClassTest.java b/src/test/java/com/android/tools/r8/resolution/PublicFieldInnerClassTest.java
index 1209624..a3e77ae 100644
--- a/src/test/java/com/android/tools/r8/resolution/PublicFieldInnerClassTest.java
+++ b/src/test/java/com/android/tools/r8/resolution/PublicFieldInnerClassTest.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/resolution/SingleStaticTargetLookupTestRunner.java b/src/test/java/com/android/tools/r8/resolution/SingleStaticTargetLookupTestRunner.java
index 0b057db..526dcca 100644
--- a/src/test/java/com/android/tools/r8/resolution/SingleStaticTargetLookupTestRunner.java
+++ b/src/test/java/com/android/tools/r8/resolution/SingleStaticTargetLookupTestRunner.java
@@ -15,10 +15,10 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRunResult;
 import com.android.tools.r8.TestShrinkerBuilder;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/resolution/SingleTargetExecutionTest.java b/src/test/java/com/android/tools/r8/resolution/SingleTargetExecutionTest.java
index 70baeaf..6e33627 100644
--- a/src/test/java/com/android/tools/r8/resolution/SingleTargetExecutionTest.java
+++ b/src/test/java/com/android/tools/r8/resolution/SingleTargetExecutionTest.java
@@ -18,7 +18,7 @@
 import com.android.tools.r8.resolution.singletarget.one.SubSubClassThree;
 import com.android.tools.r8.resolution.singletarget.one.SubSubClassTwo;
 import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/resolution/access/NestInvokeSpecialInterfaceMethodAccessTest.java b/src/test/java/com/android/tools/r8/resolution/access/NestInvokeSpecialInterfaceMethodAccessTest.java
index 0f37706..edc69ce 100644
--- a/src/test/java/com/android/tools/r8/resolution/access/NestInvokeSpecialInterfaceMethodAccessTest.java
+++ b/src/test/java/com/android/tools/r8/resolution/access/NestInvokeSpecialInterfaceMethodAccessTest.java
@@ -22,12 +22,12 @@
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.transformers.ClassFileTransformer;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.internal.BooleanUtils;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.internal.OptionalBool;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.OptionalBool;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.timing.Timing;
 import com.google.common.collect.ImmutableList;
 import java.util.Collection;
diff --git a/src/test/java/com/android/tools/r8/resolution/access/NestInvokeSpecialMethodAccessTest.java b/src/test/java/com/android/tools/r8/resolution/access/NestInvokeSpecialMethodAccessTest.java
index aff93fc..1a38ed1 100644
--- a/src/test/java/com/android/tools/r8/resolution/access/NestInvokeSpecialMethodAccessTest.java
+++ b/src/test/java/com/android/tools/r8/resolution/access/NestInvokeSpecialMethodAccessTest.java
@@ -20,11 +20,11 @@
 import com.android.tools.r8.graph.MethodResolutionResult;
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.transformers.ClassFileTransformer;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.internal.OptionalBool;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.OptionalBool;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.timing.Timing;
 import com.google.common.collect.ImmutableList;
 import java.util.Collection;
diff --git a/src/test/java/com/android/tools/r8/resolution/access/NestInvokeSpecialMethodAccessWithIntermediateTest.java b/src/test/java/com/android/tools/r8/resolution/access/NestInvokeSpecialMethodAccessWithIntermediateTest.java
index 53cae3e..652e55d 100644
--- a/src/test/java/com/android/tools/r8/resolution/access/NestInvokeSpecialMethodAccessWithIntermediateTest.java
+++ b/src/test/java/com/android/tools/r8/resolution/access/NestInvokeSpecialMethodAccessWithIntermediateTest.java
@@ -21,12 +21,12 @@
 import com.android.tools.r8.graph.MethodResolutionResult;
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.transformers.ClassFileTransformer;
-import com.android.tools.r8.utils.internal.BooleanUtils;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.internal.OptionalBool;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.OptionalBool;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.timing.Timing;
 import com.google.common.collect.ImmutableList;
 import java.util.Collection;
diff --git a/src/test/java/com/android/tools/r8/resolution/access/NestInvokeSpecialMethodPublicAccessWithIntermediateTest.java b/src/test/java/com/android/tools/r8/resolution/access/NestInvokeSpecialMethodPublicAccessWithIntermediateTest.java
index cda258c..4e62756 100644
--- a/src/test/java/com/android/tools/r8/resolution/access/NestInvokeSpecialMethodPublicAccessWithIntermediateTest.java
+++ b/src/test/java/com/android/tools/r8/resolution/access/NestInvokeSpecialMethodPublicAccessWithIntermediateTest.java
@@ -21,11 +21,11 @@
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.shaking.AppInfoWithLiveness;
 import com.android.tools.r8.transformers.ClassFileTransformer;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.internal.OptionalBool;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.OptionalBool;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.timing.Timing;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Streams;
diff --git a/src/test/java/com/android/tools/r8/resolution/access/NestStaticMethodAccessTest.java b/src/test/java/com/android/tools/r8/resolution/access/NestStaticMethodAccessTest.java
index bec9fe0..13c6f8c 100644
--- a/src/test/java/com/android/tools/r8/resolution/access/NestStaticMethodAccessTest.java
+++ b/src/test/java/com/android/tools/r8/resolution/access/NestStaticMethodAccessTest.java
@@ -19,7 +19,7 @@
 import com.android.tools.r8.transformers.ClassFileTransformer;
 import com.android.tools.r8.utils.internal.BooleanUtils;
 import com.android.tools.r8.utils.internal.OptionalBool;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.timing.Timing;
 import com.google.common.collect.ImmutableList;
 import java.util.Collection;
diff --git a/src/test/java/com/android/tools/r8/resolution/access/NestVirtualMethodAccessTest.java b/src/test/java/com/android/tools/r8/resolution/access/NestVirtualMethodAccessTest.java
index 0bf3eb2..7bfc779 100644
--- a/src/test/java/com/android/tools/r8/resolution/access/NestVirtualMethodAccessTest.java
+++ b/src/test/java/com/android/tools/r8/resolution/access/NestVirtualMethodAccessTest.java
@@ -19,7 +19,7 @@
 import com.android.tools.r8.transformers.ClassFileTransformer;
 import com.android.tools.r8.utils.internal.BooleanUtils;
 import com.android.tools.r8.utils.internal.OptionalBool;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.timing.Timing;
 import com.google.common.collect.ImmutableList;
 import java.util.Collection;
diff --git a/src/test/java/com/android/tools/r8/resolution/access/SelfVirtualMethodAccessTest.java b/src/test/java/com/android/tools/r8/resolution/access/SelfVirtualMethodAccessTest.java
index 5a98ede..ab4b23e 100644
--- a/src/test/java/com/android/tools/r8/resolution/access/SelfVirtualMethodAccessTest.java
+++ b/src/test/java/com/android/tools/r8/resolution/access/SelfVirtualMethodAccessTest.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.graph.MethodResolutionResult;
 import com.android.tools.r8.shaking.AppInfoWithLiveness;
 import com.android.tools.r8.utils.internal.OptionalBool;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.timing.Timing;
 import com.google.common.collect.ImmutableList;
 import java.util.Collection;
diff --git a/src/test/java/com/android/tools/r8/resolution/access/indirectfield/IndirectFieldAccessTest.java b/src/test/java/com/android/tools/r8/resolution/access/indirectfield/IndirectFieldAccessTest.java
index 718c580..a63c848 100644
--- a/src/test/java/com/android/tools/r8/resolution/access/indirectfield/IndirectFieldAccessTest.java
+++ b/src/test/java/com/android/tools/r8/resolution/access/indirectfield/IndirectFieldAccessTest.java
@@ -19,7 +19,7 @@
 import com.android.tools.r8.resolution.access.indirectfield.pkg.C;
 import com.android.tools.r8.shaking.AppInfoWithLiveness;
 import com.android.tools.r8.utils.internal.OptionalBool;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.timing.Timing;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/resolution/access/indirectmethod/IndirectMethodAccessTest.java b/src/test/java/com/android/tools/r8/resolution/access/indirectmethod/IndirectMethodAccessTest.java
index f0a0bd3..03c5244 100644
--- a/src/test/java/com/android/tools/r8/resolution/access/indirectmethod/IndirectMethodAccessTest.java
+++ b/src/test/java/com/android/tools/r8/resolution/access/indirectmethod/IndirectMethodAccessTest.java
@@ -16,7 +16,7 @@
 import com.android.tools.r8.resolution.access.indirectmethod.pkg.C;
 import com.android.tools.r8.shaking.AppInfoWithLiveness;
 import com.android.tools.r8.utils.internal.OptionalBool;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.timing.Timing;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
diff --git a/src/test/java/com/android/tools/r8/resolution/b123730538/B123730538.java b/src/test/java/com/android/tools/r8/resolution/b123730538/B123730538.java
index 24bc9f1..70e5583 100644
--- a/src/test/java/com/android/tools/r8/resolution/b123730538/B123730538.java
+++ b/src/test/java/com/android/tools/r8/resolution/b123730538/B123730538.java
@@ -18,12 +18,12 @@
 import com.android.tools.r8.resolution.b123730538.runner.PublicClassExtender;
 import com.android.tools.r8.resolution.b123730538.runner.Runner;
 import com.android.tools.r8.resolution.b123730538.sub.PublicClass;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Path;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/resolution/b77944861/B77944861.java b/src/test/java/com/android/tools/r8/resolution/b77944861/B77944861.java
index 631aa50..3972569 100644
--- a/src/test/java/com/android/tools/r8/resolution/b77944861/B77944861.java
+++ b/src/test/java/com/android/tools/r8/resolution/b77944861/B77944861.java
@@ -12,11 +12,11 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.resolution.b77944861.inner.TopLevelPolicy;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.FieldAccessInstructionSubject;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.Iterator;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/resolution/interfacetargets/MissingInterfaceVirtualTargetsTest.java b/src/test/java/com/android/tools/r8/resolution/interfacetargets/MissingInterfaceVirtualTargetsTest.java
index 37fa843..ecfab2c 100644
--- a/src/test/java/com/android/tools/r8/resolution/interfacetargets/MissingInterfaceVirtualTargetsTest.java
+++ b/src/test/java/com/android/tools/r8/resolution/interfacetargets/MissingInterfaceVirtualTargetsTest.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/resolution/interfacetargets/MultipleMaximallySpecificTest.java b/src/test/java/com/android/tools/r8/resolution/interfacetargets/MultipleMaximallySpecificTest.java
index 4f1ea9a..d11c3df 100644
--- a/src/test/java/com/android/tools/r8/resolution/interfacetargets/MultipleMaximallySpecificTest.java
+++ b/src/test/java/com/android/tools/r8/resolution/interfacetargets/MultipleMaximallySpecificTest.java
@@ -28,7 +28,7 @@
 import com.android.tools.r8.references.MethodReference;
 import com.android.tools.r8.shaking.AppInfoWithLiveness;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.timing.Timing;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
diff --git a/src/test/java/com/android/tools/r8/resource/DataResourceTest.java b/src/test/java/com/android/tools/r8/resource/DataResourceTest.java
index 10f1937..b0bb4b1 100644
--- a/src/test/java/com/android/tools/r8/resource/DataResourceTest.java
+++ b/src/test/java/com/android/tools/r8/resource/DataResourceTest.java
@@ -8,9 +8,9 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ToolHelper;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.TestDescriptionWatcher;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.nio.file.Paths;
 import org.junit.Rule;
diff --git a/src/test/java/com/android/tools/r8/resource/KeepDirectoriesTest.java b/src/test/java/com/android/tools/r8/resource/KeepDirectoriesTest.java
index 5d63223..f3b5a6f 100644
--- a/src/test/java/com/android/tools/r8/resource/KeepDirectoriesTest.java
+++ b/src/test/java/com/android/tools/r8/resource/KeepDirectoriesTest.java
@@ -22,7 +22,7 @@
 import com.android.tools.r8.shaking.forceproguardcompatibility.ProguardCompatibilityTestBase;
 import com.android.tools.r8.utils.AndroidApp;
 import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
diff --git a/src/test/java/com/android/tools/r8/retrace/DuplicateMappingsTest.java b/src/test/java/com/android/tools/r8/retrace/DuplicateMappingsTest.java
index 5dcca78..a2b9732 100644
--- a/src/test/java/com/android/tools/r8/retrace/DuplicateMappingsTest.java
+++ b/src/test/java/com/android/tools/r8/retrace/DuplicateMappingsTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.TestDiagnosticMessagesImpl;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/retrace/InvalidMappingRangesB309080420Test.java b/src/test/java/com/android/tools/r8/retrace/InvalidMappingRangesB309080420Test.java
index c5eaf59..43326cc 100644
--- a/src/test/java/com/android/tools/r8/retrace/InvalidMappingRangesB309080420Test.java
+++ b/src/test/java/com/android/tools/r8/retrace/InvalidMappingRangesB309080420Test.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.TestDiagnosticMessagesImpl;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/retrace/ProxyRetraceAmbiguousTest.java b/src/test/java/com/android/tools/r8/retrace/ProxyRetraceAmbiguousTest.java
index b406d4e..c18bc32 100644
--- a/src/test/java/com/android/tools/r8/retrace/ProxyRetraceAmbiguousTest.java
+++ b/src/test/java/com/android/tools/r8/retrace/ProxyRetraceAmbiguousTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.retrace.internal.StackTraceElementStringProxy;
 import com.android.tools.r8.utils.ListUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.ArrayList;
 import java.util.Collections;
diff --git a/src/test/java/com/android/tools/r8/retrace/ProxyRetraceOutlineTest.java b/src/test/java/com/android/tools/r8/retrace/ProxyRetraceOutlineTest.java
index 85d0ae0..a161b6c 100644
--- a/src/test/java/com/android/tools/r8/retrace/ProxyRetraceOutlineTest.java
+++ b/src/test/java/com/android/tools/r8/retrace/ProxyRetraceOutlineTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.retrace.internal.StackTraceElementStringProxy;
 import com.android.tools.r8.utils.ListUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.ArrayList;
 import java.util.Collections;
diff --git a/src/test/java/com/android/tools/r8/retrace/RenamedSignatureClashTest.java b/src/test/java/com/android/tools/r8/retrace/RenamedSignatureClashTest.java
index 96d52ab..fc65995 100644
--- a/src/test/java/com/android/tools/r8/retrace/RenamedSignatureClashTest.java
+++ b/src/test/java/com/android/tools/r8/retrace/RenamedSignatureClashTest.java
@@ -15,7 +15,7 @@
 import com.android.tools.r8.references.ClassReference;
 import com.android.tools.r8.references.MethodReference;
 import com.android.tools.r8.references.Reference;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/retrace/RetraceCommandLineTests.java b/src/test/java/com/android/tools/r8/retrace/RetraceCommandLineTests.java
index 9007492..139fc3f 100644
--- a/src/test/java/com/android/tools/r8/retrace/RetraceCommandLineTests.java
+++ b/src/test/java/com/android/tools/r8/retrace/RetraceCommandLineTests.java
@@ -21,7 +21,7 @@
 import com.android.tools.r8.retrace.stacktraces.FoundMethodVerboseStackTrace;
 import com.android.tools.r8.retrace.stacktraces.PGStackTrace;
 import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.ThrowingConsumer;
 import com.google.common.base.Charsets;
 import com.google.common.collect.ImmutableList;
diff --git a/src/test/java/com/android/tools/r8/retrace/RetraceIdentifiersWithNumbersTest.java b/src/test/java/com/android/tools/r8/retrace/RetraceIdentifiersWithNumbersTest.java
index 3d41638..8ca3037 100644
--- a/src/test/java/com/android/tools/r8/retrace/RetraceIdentifiersWithNumbersTest.java
+++ b/src/test/java/com/android/tools/r8/retrace/RetraceIdentifiersWithNumbersTest.java
@@ -15,7 +15,7 @@
 import com.android.tools.r8.naming.retrace.StackTrace;
 import com.android.tools.r8.naming.retrace.StackTrace.StackTraceLine;
 import com.android.tools.r8.naming.retrace.StackTraceLineProxy;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/retrace/RetraceMappingWithOverloadsTest.java b/src/test/java/com/android/tools/r8/retrace/RetraceMappingWithOverloadsTest.java
index efd547d..eff3f49 100644
--- a/src/test/java/com/android/tools/r8/retrace/RetraceMappingWithOverloadsTest.java
+++ b/src/test/java/com/android/tools/r8/retrace/RetraceMappingWithOverloadsTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.references.ClassReference;
 import com.android.tools.r8.references.Reference;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import java.util.stream.Collectors;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/retrace/RetraceNestAccessorTest.java b/src/test/java/com/android/tools/r8/retrace/RetraceNestAccessorTest.java
index 9f38df7..4ebeccd 100644
--- a/src/test/java/com/android/tools/r8/retrace/RetraceNestAccessorTest.java
+++ b/src/test/java/com/android/tools/r8/retrace/RetraceNestAccessorTest.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/retrace/RetraceSyntheticClassWithNonSyntheticMethodTest.java b/src/test/java/com/android/tools/r8/retrace/RetraceSyntheticClassWithNonSyntheticMethodTest.java
index 9b8a324..8d15fc8 100644
--- a/src/test/java/com/android/tools/r8/retrace/RetraceSyntheticClassWithNonSyntheticMethodTest.java
+++ b/src/test/java/com/android/tools/r8/retrace/RetraceSyntheticClassWithNonSyntheticMethodTest.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.references.ClassReference;
 import com.android.tools.r8.references.Reference;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import java.util.stream.Collectors;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/retrace/RetraceTests.java b/src/test/java/com/android/tools/r8/retrace/RetraceTests.java
index 48d0e24..e07faf9 100644
--- a/src/test/java/com/android/tools/r8/retrace/RetraceTests.java
+++ b/src/test/java/com/android/tools/r8/retrace/RetraceTests.java
@@ -88,7 +88,7 @@
 import com.android.tools.r8.retrace.stacktraces.UnknownSourceStackTrace;
 import com.android.tools.r8.retrace.stacktraces.VerboseUnknownStackTrace;
 import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.File;
 import java.nio.charset.StandardCharsets;
diff --git a/src/test/java/com/android/tools/r8/retrace/RetraceWhitespaceTest.java b/src/test/java/com/android/tools/r8/retrace/RetraceWhitespaceTest.java
index 17b6600..350b076 100644
--- a/src/test/java/com/android/tools/r8/retrace/RetraceWhitespaceTest.java
+++ b/src/test/java/com/android/tools/r8/retrace/RetraceWhitespaceTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.ToolHelper.ProcessResult;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
diff --git a/src/test/java/com/android/tools/r8/retrace/StackTraceRegularExpressionParserTests.java b/src/test/java/com/android/tools/r8/retrace/StackTraceRegularExpressionParserTests.java
index 3131325..4d94be8 100644
--- a/src/test/java/com/android/tools/r8/retrace/StackTraceRegularExpressionParserTests.java
+++ b/src/test/java/com/android/tools/r8/retrace/StackTraceRegularExpressionParserTests.java
@@ -15,7 +15,7 @@
 import com.android.tools.r8.retrace.stacktraces.RetraceAssertionErrorStackTrace;
 import com.android.tools.r8.retrace.stacktraces.StackTraceForTest;
 import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.Collections;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/retrace/StringRetraceAmbiguousTest.java b/src/test/java/com/android/tools/r8/retrace/StringRetraceAmbiguousTest.java
index a092b7d..75705a8 100644
--- a/src/test/java/com/android/tools/r8/retrace/StringRetraceAmbiguousTest.java
+++ b/src/test/java/com/android/tools/r8/retrace/StringRetraceAmbiguousTest.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.ArrayList;
 import java.util.Collections;
diff --git a/src/test/java/com/android/tools/r8/retrace/StringRetraceOutlineTest.java b/src/test/java/com/android/tools/r8/retrace/StringRetraceOutlineTest.java
index 475a131..b218e4c 100644
--- a/src/test/java/com/android/tools/r8/retrace/StringRetraceOutlineTest.java
+++ b/src/test/java/com/android/tools/r8/retrace/StringRetraceOutlineTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.ArrayList;
 import java.util.Collections;
diff --git a/src/test/java/com/android/tools/r8/retrace/api/RetraceApiTypeResultTest.java b/src/test/java/com/android/tools/r8/retrace/api/RetraceApiTypeResultTest.java
index 3678f63..3058539 100644
--- a/src/test/java/com/android/tools/r8/retrace/api/RetraceApiTypeResultTest.java
+++ b/src/test/java/com/android/tools/r8/retrace/api/RetraceApiTypeResultTest.java
@@ -32,7 +32,7 @@
 import com.android.tools.r8.retrace.StackTraceElementProxy;
 import com.android.tools.r8.retrace.StackTraceLineParser;
 import com.android.tools.r8.utils.internal.BooleanBox;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.HashSet;
diff --git a/src/test/java/com/android/tools/r8/retrace/api/RetracePartitionStackTracePromiseTest.java b/src/test/java/com/android/tools/r8/retrace/api/RetracePartitionStackTracePromiseTest.java
index b361282..333a3a6 100644
--- a/src/test/java/com/android/tools/r8/retrace/api/RetracePartitionStackTracePromiseTest.java
+++ b/src/test/java/com/android/tools/r8/retrace/api/RetracePartitionStackTracePromiseTest.java
@@ -25,7 +25,7 @@
 import com.android.tools.r8.retrace.api.RetraceApiTypeResultTest.RetracePartitionStackTraceTest;
 import com.android.tools.r8.retrace.api.RetraceApiTypeResultTest.RetracePartitionStackTraceTest.IdentityStackTraceLineParser;
 import com.android.tools.r8.utils.internal.Box;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/retrace/mappings/FieldsWithSameMinifiedNameMapping.java b/src/test/java/com/android/tools/r8/retrace/mappings/FieldsWithSameMinifiedNameMapping.java
index 0e340bb..969ae78 100644
--- a/src/test/java/com/android/tools/r8/retrace/mappings/FieldsWithSameMinifiedNameMapping.java
+++ b/src/test/java/com/android/tools/r8/retrace/mappings/FieldsWithSameMinifiedNameMapping.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.retrace.RetraceFieldResult;
 import com.android.tools.r8.retrace.Retracer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import java.util.stream.Collectors;
diff --git a/src/test/java/com/android/tools/r8/retrace/partition/RetracePartitionAndJoinIdentityTest.java b/src/test/java/com/android/tools/r8/retrace/partition/RetracePartitionAndJoinIdentityTest.java
index f4a9316..e8c953e 100644
--- a/src/test/java/com/android/tools/r8/retrace/partition/RetracePartitionAndJoinIdentityTest.java
+++ b/src/test/java/com/android/tools/r8/retrace/partition/RetracePartitionAndJoinIdentityTest.java
@@ -17,7 +17,7 @@
 import com.android.tools.r8.retrace.ProguardMapProducer;
 import com.android.tools.r8.retrace.internal.MappingPartitionKeyStrategy;
 import com.android.tools.r8.retrace.internal.ProguardMapPartitionerOnClassNameToText.ProguardMapPartitionerBuilderImplInternal;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.util.HashMap;
diff --git a/src/test/java/com/android/tools/r8/retrace/partition/RetracePartitionFormatsTest.java b/src/test/java/com/android/tools/r8/retrace/partition/RetracePartitionFormatsTest.java
index f7a29d8..f0a7412 100644
--- a/src/test/java/com/android/tools/r8/retrace/partition/RetracePartitionFormatsTest.java
+++ b/src/test/java/com/android/tools/r8/retrace/partition/RetracePartitionFormatsTest.java
@@ -16,8 +16,8 @@
 import com.android.tools.r8.ToolHelper.ProcessResult;
 import com.android.tools.r8.retrace.Retrace;
 import com.android.tools.r8.retrace.RetraceCommand;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.PartitionMapZipContainer;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.nio.charset.StandardCharsets;
diff --git a/src/test/java/com/android/tools/r8/retrace/partition/RetracePartitionMetadataPartitionNamesTest.java b/src/test/java/com/android/tools/r8/retrace/partition/RetracePartitionMetadataPartitionNamesTest.java
index 2f5bc20..83fc7ae 100644
--- a/src/test/java/com/android/tools/r8/retrace/partition/RetracePartitionMetadataPartitionNamesTest.java
+++ b/src/test/java/com/android/tools/r8/retrace/partition/RetracePartitionMetadataPartitionNamesTest.java
@@ -21,7 +21,7 @@
 import com.android.tools.r8.retrace.internal.MappingPartitionKeyStrategy;
 import com.android.tools.r8.retrace.internal.MappingPartitionMetadataInternal;
 import com.android.tools.r8.retrace.internal.ProguardMapPartitionerOnClassNameToText.ProguardMapPartitionerBuilderImplInternal;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.HashSet;
diff --git a/src/test/java/com/android/tools/r8/retrace/partition/RetracePartitionMultipleOutlineClassTest.java b/src/test/java/com/android/tools/r8/retrace/partition/RetracePartitionMultipleOutlineClassTest.java
index 24dfbf3..2b026c2 100644
--- a/src/test/java/com/android/tools/r8/retrace/partition/RetracePartitionMultipleOutlineClassTest.java
+++ b/src/test/java/com/android/tools/r8/retrace/partition/RetracePartitionMultipleOutlineClassTest.java
@@ -21,7 +21,7 @@
 import com.android.tools.r8.retrace.RetraceFrameElement;
 import com.android.tools.r8.retrace.RetraceStackTraceContext;
 import com.android.tools.r8.retrace.Retracer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.util.Arrays;
 import java.util.HashMap;
diff --git a/src/test/java/com/android/tools/r8/retrace/partition/RetracePartitionNoMapVersionTest.java b/src/test/java/com/android/tools/r8/retrace/partition/RetracePartitionNoMapVersionTest.java
index 412c7c8..e6c582c 100644
--- a/src/test/java/com/android/tools/r8/retrace/partition/RetracePartitionNoMapVersionTest.java
+++ b/src/test/java/com/android/tools/r8/retrace/partition/RetracePartitionNoMapVersionTest.java
@@ -23,7 +23,7 @@
 import com.android.tools.r8.retrace.RetracedSingleFrame;
 import com.android.tools.r8.retrace.Retracer;
 import com.android.tools.r8.retrace.internal.MappingPartitionMetadataInternal;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.util.HashMap;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/retrace/partition/RetracePartitionWithPrimitiveNameTest.java b/src/test/java/com/android/tools/r8/retrace/partition/RetracePartitionWithPrimitiveNameTest.java
index e848753..70ab737 100644
--- a/src/test/java/com/android/tools/r8/retrace/partition/RetracePartitionWithPrimitiveNameTest.java
+++ b/src/test/java/com/android/tools/r8/retrace/partition/RetracePartitionWithPrimitiveNameTest.java
@@ -19,7 +19,7 @@
 import com.android.tools.r8.retrace.StringRetrace;
 import com.android.tools.r8.retrace.internal.MappingPartitionKeyStrategy;
 import com.android.tools.r8.retrace.internal.ProguardMapPartitionerOnClassNameToText.ProguardMapPartitionerBuilderImplInternal;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.HashMap;
 import java.util.Map;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/retrace/stacksamples/HorizontalClassMergingStackSampleRetraceTest.java b/src/test/java/com/android/tools/r8/retrace/stacksamples/HorizontalClassMergingStackSampleRetraceTest.java
index 0a43112..d457552 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacksamples/HorizontalClassMergingStackSampleRetraceTest.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacksamples/HorizontalClassMergingStackSampleRetraceTest.java
@@ -17,11 +17,11 @@
 import com.android.tools.r8.retrace.RetraceElement;
 import com.android.tools.r8.retrace.RetraceMethodElement;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.HorizontallyMergedClassesInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableSet;
 import java.util.List;
 import java.util.Set;
diff --git a/src/test/java/com/android/tools/r8/retrace/stacksamples/MethodWithInlinePositionsStackSampleRetraceTest.java b/src/test/java/com/android/tools/r8/retrace/stacksamples/MethodWithInlinePositionsStackSampleRetraceTest.java
index 780fd12..a29c5e2 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacksamples/MethodWithInlinePositionsStackSampleRetraceTest.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacksamples/MethodWithInlinePositionsStackSampleRetraceTest.java
@@ -10,9 +10,9 @@
 import com.android.tools.r8.R8TestCompileResultBase;
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.retrace.RetraceMethodElement;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.BeforeClass;
 import org.junit.Test;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacksamples/MethodWithOverloadStackSampleRetraceTest.java b/src/test/java/com/android/tools/r8/retrace/stacksamples/MethodWithOverloadStackSampleRetraceTest.java
index 1d71a1e..4ea501b 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacksamples/MethodWithOverloadStackSampleRetraceTest.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacksamples/MethodWithOverloadStackSampleRetraceTest.java
@@ -15,11 +15,11 @@
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.retrace.RetraceElement;
 import com.android.tools.r8.retrace.RetraceMethodElement;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableSet;
 import java.util.List;
 import java.util.Set;
diff --git a/src/test/java/com/android/tools/r8/retrace/stacksamples/MethodWithRemovedArgumentStackSampleRetraceTest.java b/src/test/java/com/android/tools/r8/retrace/stacksamples/MethodWithRemovedArgumentStackSampleRetraceTest.java
index 9b4bef0..eec2fba 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacksamples/MethodWithRemovedArgumentStackSampleRetraceTest.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacksamples/MethodWithRemovedArgumentStackSampleRetraceTest.java
@@ -11,10 +11,10 @@
 import com.android.tools.r8.R8TestCompileResultBase;
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.retrace.RetraceMethodElement;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.BeforeClass;
 import org.junit.Test;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacksamples/StackSampleRetraceTestBase.java b/src/test/java/com/android/tools/r8/retrace/stacksamples/StackSampleRetraceTestBase.java
index be08381..2857656 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacksamples/StackSampleRetraceTestBase.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacksamples/StackSampleRetraceTestBase.java
@@ -4,7 +4,7 @@
 package com.android.tools.r8.retrace.stacksamples;
 
 import static com.android.tools.r8.utils.InternalOptions.ASM_VERSION;
-import static com.android.tools.r8.utils.StringUtils.UNIX_LINE_SEPARATOR;
+import static com.android.tools.r8.utils.internal.StringUtils.UNIX_LINE_SEPARATOR;
 import static org.junit.Assert.assertEquals;
 
 import com.android.tools.r8.R8TestBuilder;
@@ -22,11 +22,11 @@
 import com.android.tools.r8.retrace.RetraceMethodElement;
 import com.android.tools.r8.retrace.RetraceMethodResult;
 import com.android.tools.r8.retrace.Retracer;
-import com.android.tools.r8.utils.internal.BooleanBox;
-import com.android.tools.r8.utils.internal.IntBox;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.HorizontallyMergedClassesInspector;
+import com.android.tools.r8.utils.internal.BooleanBox;
+import com.android.tools.r8.utils.internal.IntBox;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import java.util.stream.Collectors;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/retrace/stacksamples/StaticizedMethodStackSampleRetraceTest.java b/src/test/java/com/android/tools/r8/retrace/stacksamples/StaticizedMethodStackSampleRetraceTest.java
index 7574d25..5a09421 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacksamples/StaticizedMethodStackSampleRetraceTest.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacksamples/StaticizedMethodStackSampleRetraceTest.java
@@ -13,10 +13,10 @@
 import com.android.tools.r8.R8TestCompileResultBase;
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.retrace.RetraceMethodElement;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.BeforeClass;
 import org.junit.Test;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacksamples/VerticalClassMergingStackSampleRetraceTest.java b/src/test/java/com/android/tools/r8/retrace/stacksamples/VerticalClassMergingStackSampleRetraceTest.java
index 7651c90..37c0687 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacksamples/VerticalClassMergingStackSampleRetraceTest.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacksamples/VerticalClassMergingStackSampleRetraceTest.java
@@ -14,10 +14,10 @@
 import com.android.tools.r8.R8TestCompileResultBase;
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.retrace.RetraceMethodElement;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/AmbiguousInlineFramesStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/AmbiguousInlineFramesStackTrace.java
index 85cb682..9dfdc1b 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/AmbiguousInlineFramesStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/AmbiguousInlineFramesStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/AmbiguousMethodVerboseStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/AmbiguousMethodVerboseStackTrace.java
index 51acd54..03c1115 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/AmbiguousMethodVerboseStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/AmbiguousMethodVerboseStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/AmbiguousMissingLineStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/AmbiguousMissingLineStackTrace.java
index 2e2a527..ef44cae 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/AmbiguousMissingLineStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/AmbiguousMissingLineStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/AmbiguousMultipleInlineStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/AmbiguousMultipleInlineStackTrace.java
index abf5ba6..c0364d5 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/AmbiguousMultipleInlineStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/AmbiguousMultipleInlineStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/AmbiguousStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/AmbiguousStackTrace.java
index a5241a8..fe8b30d 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/AmbiguousStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/AmbiguousStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/AmbiguousWithMultipleLineMappingsStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/AmbiguousWithMultipleLineMappingsStackTrace.java
index 1041ace..a809cbd 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/AmbiguousWithMultipleLineMappingsStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/AmbiguousWithMultipleLineMappingsStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/AmbiguousWithSignatureStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/AmbiguousWithSignatureStackTrace.java
index 1f0cd0c..bc30a99 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/AmbiguousWithSignatureStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/AmbiguousWithSignatureStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/AutoStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/AutoStackTrace.java
index ab7f261..777c9a1 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/AutoStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/AutoStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/CircularReferenceStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/CircularReferenceStackTrace.java
index 00d8332..2e4a44f 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/CircularReferenceStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/CircularReferenceStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/ClassWithDashStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/ClassWithDashStackTrace.java
index 07fb551..fc036aa 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/ClassWithDashStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/ClassWithDashStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/DifferentLineNumberSpanStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/DifferentLineNumberSpanStackTrace.java
index ef9853e..64aa72b 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/DifferentLineNumberSpanStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/DifferentLineNumberSpanStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/FileNameExtensionStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/FileNameExtensionStackTrace.java
index 6d99ef0..099718e 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/FileNameExtensionStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/FileNameExtensionStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/FoundMethodVerboseStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/FoundMethodVerboseStackTrace.java
index b4812a5..fe814b0 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/FoundMethodVerboseStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/FoundMethodVerboseStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/IdentityMappingStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/IdentityMappingStackTrace.java
index 40992ae..766ad52 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/IdentityMappingStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/IdentityMappingStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineFileNameStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineFileNameStackTrace.java
index b8243aa..0e8c4c7 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineFileNameStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineFileNameStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineFileNameWithInnerClassesStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineFileNameWithInnerClassesStackTrace.java
index 1c53b40..9048523 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineFileNameWithInnerClassesStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineFileNameWithInnerClassesStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineInOutlineStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineInOutlineStackTrace.java
index df74712..31565b5 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineInOutlineStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineInOutlineStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineNoLineAssumeNoInlineAmbiguousStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineNoLineAssumeNoInlineAmbiguousStackTrace.java
index 7c63a27..ef7bea4 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineNoLineAssumeNoInlineAmbiguousStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineNoLineAssumeNoInlineAmbiguousStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineNoLineNumberAssumeNoInlineStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineNoLineNumberAssumeNoInlineStackTrace.java
index 9382f6e..e9643a8 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineNoLineNumberAssumeNoInlineStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineNoLineNumberAssumeNoInlineStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineNoLineNumberStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineNoLineNumberStackTrace.java
index 28e94c5..67087ee 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineNoLineNumberStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineNoLineNumberStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineNoLineWithBaseEntryNumberAssumeNoInlineStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineNoLineWithBaseEntryNumberAssumeNoInlineStackTrace.java
index 3e6de74..bb397f3 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineNoLineWithBaseEntryNumberAssumeNoInlineStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineNoLineWithBaseEntryNumberAssumeNoInlineStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/InlinePreambleNoOriginalStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/InlinePreambleNoOriginalStackTrace.java
index 79a9172..2e37f51 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/InlinePreambleNoOriginalStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/InlinePreambleNoOriginalStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineRemoveFrameJava17StackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineRemoveFrameJava17StackTrace.java
index b899077..022aa4d 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineRemoveFrameJava17StackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineRemoveFrameJava17StackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineSourceFileContextStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineSourceFileContextStackTrace.java
index f5943b5..b63c66a 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineSourceFileContextStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineSourceFileContextStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineSourceFileStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineSourceFileStackTrace.java
index 9128e47..d08abd2 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineSourceFileStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineSourceFileStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineWithLineNumbersStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineWithLineNumbersStackTrace.java
index eb1144e..97defe8 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineWithLineNumbersStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/InlineWithLineNumbersStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/InvalidMinifiedRangeStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/InvalidMinifiedRangeStackTrace.java
index 92e6567..a027deb 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/InvalidMinifiedRangeStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/InvalidMinifiedRangeStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/InvalidOriginalRangeStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/InvalidOriginalRangeStackTrace.java
index 9a6bcde..84c2d33 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/InvalidOriginalRangeStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/InvalidOriginalRangeStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/MapVersionWarningStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/MapVersionWarningStackTrace.java
index 094ebd7..29e8da5 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/MapVersionWarningStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/MapVersionWarningStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/MemberFieldOverlapStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/MemberFieldOverlapStackTrace.java
index ca6b1c9..fff0ce8 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/MemberFieldOverlapStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/MemberFieldOverlapStackTrace.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.retrace.RetraceFieldElement;
 import com.android.tools.r8.retrace.RetraceFieldResult;
 import com.android.tools.r8.retrace.Retracer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 import java.util.Optional;
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/MovedSynthetizedInfoStackTraceTest.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/MovedSynthetizedInfoStackTraceTest.java
index 75724b3..9f28ed1 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/MovedSynthetizedInfoStackTraceTest.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/MovedSynthetizedInfoStackTraceTest.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/MultipleLinesNoLineNumberStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/MultipleLinesNoLineNumberStackTrace.java
index 3f5746d..0d148cf 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/MultipleLinesNoLineNumberStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/MultipleLinesNoLineNumberStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/MultipleMapVersionsWarningStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/MultipleMapVersionsWarningStackTrace.java
index 63717a7..03767dc 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/MultipleMapVersionsWarningStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/MultipleMapVersionsWarningStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/MultipleOriginalLinesNoLineNumberStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/MultipleOriginalLinesNoLineNumberStackTrace.java
index 93a3567..051756c 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/MultipleOriginalLinesNoLineNumberStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/MultipleOriginalLinesNoLineNumberStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/NamedModuleStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/NamedModuleStackTrace.java
index 10c73c4..5dbf84e 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/NamedModuleStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/NamedModuleStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/NoObfuscatedLineNumberWithOverrideTest.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/NoObfuscatedLineNumberWithOverrideTest.java
index d444bcf..4039bc5 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/NoObfuscatedLineNumberWithOverrideTest.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/NoObfuscatedLineNumberWithOverrideTest.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/NoObfuscationRangeMappingWithStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/NoObfuscationRangeMappingWithStackTrace.java
index 67a0d43..24468a8 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/NoObfuscationRangeMappingWithStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/NoObfuscationRangeMappingWithStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/NpeInlineRetraceStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/NpeInlineRetraceStackTrace.java
index 6e9a0be..0e8718e 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/NpeInlineRetraceStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/NpeInlineRetraceStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/ObfuscatedRangeToSingleLineStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/ObfuscatedRangeToSingleLineStackTrace.java
index e87126f..b51a8f2 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/ObfuscatedRangeToSingleLineStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/ObfuscatedRangeToSingleLineStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/OutlineInOutlineStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/OutlineInOutlineStackTrace.java
index 95e5185..56e80af 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/OutlineInOutlineStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/OutlineInOutlineStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/OutlineSimpleStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/OutlineSimpleStackTrace.java
index b8109cf..73aee11 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/OutlineSimpleStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/OutlineSimpleStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/OutlineWithInliningStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/OutlineWithInliningStackTrace.java
index 238a7d1..ec76f77 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/OutlineWithInliningStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/OutlineWithInliningStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/OutsideLineRangeStackTraceTest.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/OutsideLineRangeStackTraceTest.java
index 2ebf79a..9082cd2 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/OutsideLineRangeStackTraceTest.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/OutsideLineRangeStackTraceTest.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/OverloadSameLineTest.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/OverloadSameLineTest.java
index ec69283..02c0a29 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/OverloadSameLineTest.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/OverloadSameLineTest.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/OverloadedWithAndWithoutRangeStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/OverloadedWithAndWithoutRangeStackTrace.java
index 4c6dc4a..1ef8298 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/OverloadedWithAndWithoutRangeStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/OverloadedWithAndWithoutRangeStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/PGStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/PGStackTrace.java
index 2a3a63a..de78434 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/PGStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/PGStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/PreambleLineNumberStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/PreambleLineNumberStackTrace.java
index bbd72bd..df96d56 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/PreambleLineNumberStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/PreambleLineNumberStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/ResidualSignatureOnOuterFrameStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/ResidualSignatureOnOuterFrameStackTrace.java
index f464a62..c3669ca 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/ResidualSignatureOnOuterFrameStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/ResidualSignatureOnOuterFrameStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Collections;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/RetraceAssertionErrorStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/RetraceAssertionErrorStackTrace.java
index 11d2669..dd19fc3 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/RetraceAssertionErrorStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/RetraceAssertionErrorStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/SingleLineNoLineNumberStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/SingleLineNoLineNumberStackTrace.java
index a78d417..28d032a 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/SingleLineNoLineNumberStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/SingleLineNoLineNumberStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/SourceFileNameSynthesizeStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/SourceFileNameSynthesizeStackTrace.java
index 9e15a2d..2d6caf4 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/SourceFileNameSynthesizeStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/SourceFileNameSynthesizeStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/SourceFileWithNumberAndEmptyStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/SourceFileWithNumberAndEmptyStackTrace.java
index fd20517..cce435b 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/SourceFileWithNumberAndEmptyStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/SourceFileWithNumberAndEmptyStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/SyntheticLambdaMethodStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/SyntheticLambdaMethodStackTrace.java
index fc7a1e5..6bb0efe 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/SyntheticLambdaMethodStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/SyntheticLambdaMethodStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/SyntheticLambdaMethodWithInliningStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/SyntheticLambdaMethodWithInliningStackTrace.java
index bd92f9f..cb3fa8b 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/SyntheticLambdaMethodWithInliningStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/SyntheticLambdaMethodWithInliningStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/TrailingWhitespaceStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/TrailingWhitespaceStackTrace.java
index bfc7476..977c851 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/TrailingWhitespaceStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/TrailingWhitespaceStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/retrace/stacktraces/UnknownSourceStackTrace.java b/src/test/java/com/android/tools/r8/retrace/stacktraces/UnknownSourceStackTrace.java
index a55423e..9765839 100644
--- a/src/test/java/com/android/tools/r8/retrace/stacktraces/UnknownSourceStackTrace.java
+++ b/src/test/java/com/android/tools/r8/retrace/stacktraces/UnknownSourceStackTrace.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.retrace.stacktraces;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/rewrite/JavaScriptScriptEngineTest.java b/src/test/java/com/android/tools/r8/rewrite/JavaScriptScriptEngineTest.java
index 4af8c94..41a5220 100644
--- a/src/test/java/com/android/tools/r8/rewrite/JavaScriptScriptEngineTest.java
+++ b/src/test/java/com/android/tools/r8/rewrite/JavaScriptScriptEngineTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.util.concurrent.ExecutionException;
 import javax.script.ScriptEngine;
diff --git a/src/test/java/com/android/tools/r8/rewrite/ScriptEngineTest.java b/src/test/java/com/android/tools/r8/rewrite/ScriptEngineTest.java
index 3046451..a976afa 100644
--- a/src/test/java/com/android/tools/r8/rewrite/ScriptEngineTest.java
+++ b/src/test/java/com/android/tools/r8/rewrite/ScriptEngineTest.java
@@ -19,7 +19,7 @@
 import com.android.tools.r8.ToolHelper.DexVm.Version;
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.utils.internal.StreamUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.io.Reader;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/rewrite/arrays/ArrayOfArraysTest.java b/src/test/java/com/android/tools/r8/rewrite/arrays/ArrayOfArraysTest.java
index 26a4674..eea4616 100644
--- a/src/test/java/com/android/tools/r8/rewrite/arrays/ArrayOfArraysTest.java
+++ b/src/test/java/com/android/tools/r8/rewrite/arrays/ArrayOfArraysTest.java
@@ -10,10 +10,10 @@
 import com.android.tools.r8.NeverInline;
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/rewrite/arrays/ArrayOfConstClassArraysTest.java b/src/test/java/com/android/tools/r8/rewrite/arrays/ArrayOfConstClassArraysTest.java
index d2afb69..32829b5 100644
--- a/src/test/java/com/android/tools/r8/rewrite/arrays/ArrayOfConstClassArraysTest.java
+++ b/src/test/java/com/android/tools/r8/rewrite/arrays/ArrayOfConstClassArraysTest.java
@@ -10,10 +10,10 @@
 import com.android.tools.r8.NeverInline;
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/rewrite/arrays/ArrayOfIntArraysTest.java b/src/test/java/com/android/tools/r8/rewrite/arrays/ArrayOfIntArraysTest.java
index c429641..ab17590 100644
--- a/src/test/java/com/android/tools/r8/rewrite/arrays/ArrayOfIntArraysTest.java
+++ b/src/test/java/com/android/tools/r8/rewrite/arrays/ArrayOfIntArraysTest.java
@@ -10,10 +10,10 @@
 import com.android.tools.r8.NeverInline;
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/rewrite/arrays/ArrayOfStringArraysTest.java b/src/test/java/com/android/tools/r8/rewrite/arrays/ArrayOfStringArraysTest.java
index 5aaed9c..711c116 100644
--- a/src/test/java/com/android/tools/r8/rewrite/arrays/ArrayOfStringArraysTest.java
+++ b/src/test/java/com/android/tools/r8/rewrite/arrays/ArrayOfStringArraysTest.java
@@ -10,10 +10,10 @@
 import com.android.tools.r8.NeverInline;
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/rewrite/arrays/ConstClassArrayTest.java b/src/test/java/com/android/tools/r8/rewrite/arrays/ConstClassArrayTest.java
index c27a171..55982dd 100644
--- a/src/test/java/com/android/tools/r8/rewrite/arrays/ConstClassArrayTest.java
+++ b/src/test/java/com/android/tools/r8/rewrite/arrays/ConstClassArrayTest.java
@@ -10,10 +10,10 @@
 import com.android.tools.r8.NeverInline;
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Iterator;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/rewrite/arrays/ConstClassArrayWithNonUniqueValuesTest.java b/src/test/java/com/android/tools/r8/rewrite/arrays/ConstClassArrayWithNonUniqueValuesTest.java
index 9459997..e489f90 100644
--- a/src/test/java/com/android/tools/r8/rewrite/arrays/ConstClassArrayWithNonUniqueValuesTest.java
+++ b/src/test/java/com/android/tools/r8/rewrite/arrays/ConstClassArrayWithNonUniqueValuesTest.java
@@ -13,10 +13,10 @@
 import com.android.tools.r8.TestCompilerBuilder;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.dex.Constants;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.Arrays;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/rewrite/arrays/ConstClassArrayWithUniqueValuesTest.java b/src/test/java/com/android/tools/r8/rewrite/arrays/ConstClassArrayWithUniqueValuesTest.java
index 3c7976f..b32d982 100644
--- a/src/test/java/com/android/tools/r8/rewrite/arrays/ConstClassArrayWithUniqueValuesTest.java
+++ b/src/test/java/com/android/tools/r8/rewrite/arrays/ConstClassArrayWithUniqueValuesTest.java
@@ -11,10 +11,10 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.dex.Constants;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.Arrays;
 import java.util.Iterator;
diff --git a/src/test/java/com/android/tools/r8/rewrite/arrays/IntegerArrayTest.java b/src/test/java/com/android/tools/r8/rewrite/arrays/IntegerArrayTest.java
index 1c159da..3cd385d 100644
--- a/src/test/java/com/android/tools/r8/rewrite/arrays/IntegerArrayTest.java
+++ b/src/test/java/com/android/tools/r8/rewrite/arrays/IntegerArrayTest.java
@@ -10,10 +10,10 @@
 import com.android.tools.r8.NeverInline;
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/rewrite/arrays/NewArrayInSameCatchRangeTest.java b/src/test/java/com/android/tools/r8/rewrite/arrays/NewArrayInSameCatchRangeTest.java
index 1eb6031..d0dc523 100644
--- a/src/test/java/com/android/tools/r8/rewrite/arrays/NewArrayInSameCatchRangeTest.java
+++ b/src/test/java/com/android/tools/r8/rewrite/arrays/NewArrayInSameCatchRangeTest.java
@@ -9,9 +9,9 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.dex.code.DexFilledNewArray;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/rewrite/arrays/NewArraySynchronizedBlockTest.java b/src/test/java/com/android/tools/r8/rewrite/arrays/NewArraySynchronizedBlockTest.java
index 13c7558..3529de3 100644
--- a/src/test/java/com/android/tools/r8/rewrite/arrays/NewArraySynchronizedBlockTest.java
+++ b/src/test/java/com/android/tools/r8/rewrite/arrays/NewArraySynchronizedBlockTest.java
@@ -9,10 +9,10 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.dex.code.DexFilledNewArray;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import java.util.stream.Collectors;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/rewrite/arrays/StaticGetArrayWithNonUniqueValuesTest.java b/src/test/java/com/android/tools/r8/rewrite/arrays/StaticGetArrayWithNonUniqueValuesTest.java
index 68b80fc..fcf2bfc 100644
--- a/src/test/java/com/android/tools/r8/rewrite/arrays/StaticGetArrayWithNonUniqueValuesTest.java
+++ b/src/test/java/com/android/tools/r8/rewrite/arrays/StaticGetArrayWithNonUniqueValuesTest.java
@@ -12,10 +12,10 @@
 import com.android.tools.r8.TestCompilerBuilder;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.dex.Constants;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.Arrays;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/rewrite/arrays/StaticGetArrayWithUniqueValuesTest.java b/src/test/java/com/android/tools/r8/rewrite/arrays/StaticGetArrayWithUniqueValuesTest.java
index f64d0e8..f1e03a1 100644
--- a/src/test/java/com/android/tools/r8/rewrite/arrays/StaticGetArrayWithUniqueValuesTest.java
+++ b/src/test/java/com/android/tools/r8/rewrite/arrays/StaticGetArrayWithUniqueValuesTest.java
@@ -11,10 +11,10 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.dex.Constants;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.Arrays;
 import java.util.Iterator;
diff --git a/src/test/java/com/android/tools/r8/rewrite/arrays/StringArrayWithNonUniqueValuesTest.java b/src/test/java/com/android/tools/r8/rewrite/arrays/StringArrayWithNonUniqueValuesTest.java
index cf12961..455b2b9 100644
--- a/src/test/java/com/android/tools/r8/rewrite/arrays/StringArrayWithNonUniqueValuesTest.java
+++ b/src/test/java/com/android/tools/r8/rewrite/arrays/StringArrayWithNonUniqueValuesTest.java
@@ -12,10 +12,10 @@
 import com.android.tools.r8.TestCompilerBuilder;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.dex.Constants;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.Arrays;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/rewrite/arrays/StringArrayWithUniqueValuesTest.java b/src/test/java/com/android/tools/r8/rewrite/arrays/StringArrayWithUniqueValuesTest.java
index 53f7f1f..b7ab2e8 100644
--- a/src/test/java/com/android/tools/r8/rewrite/arrays/StringArrayWithUniqueValuesTest.java
+++ b/src/test/java/com/android/tools/r8/rewrite/arrays/StringArrayWithUniqueValuesTest.java
@@ -11,10 +11,10 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.dex.Constants;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.Arrays;
 import java.util.Iterator;
diff --git a/src/test/java/com/android/tools/r8/rewrite/assertions/AssertionConfigurationAssertionHandlerAssertionInClinitOnlyTest.java b/src/test/java/com/android/tools/r8/rewrite/assertions/AssertionConfigurationAssertionHandlerAssertionInClinitOnlyTest.java
index 160d344..609622f 100644
--- a/src/test/java/com/android/tools/r8/rewrite/assertions/AssertionConfigurationAssertionHandlerAssertionInClinitOnlyTest.java
+++ b/src/test/java/com/android/tools/r8/rewrite/assertions/AssertionConfigurationAssertionHandlerAssertionInClinitOnlyTest.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.rewrite.assertions.assertionhandler.AssertionHandlers;
 import com.android.tools.r8.rewrite.assertions.assertionhandler.AssertionsInClinit;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/rewrite/assertions/AssertionConfigurationAssertionHandlerMissingClassTest.java b/src/test/java/com/android/tools/r8/rewrite/assertions/AssertionConfigurationAssertionHandlerMissingClassTest.java
index 4b1b56d..b38af53 100644
--- a/src/test/java/com/android/tools/r8/rewrite/assertions/AssertionConfigurationAssertionHandlerMissingClassTest.java
+++ b/src/test/java/com/android/tools/r8/rewrite/assertions/AssertionConfigurationAssertionHandlerMissingClassTest.java
@@ -14,8 +14,8 @@
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.rewrite.assertions.assertionhandler.AssertionHandlers;
 import com.android.tools.r8.rewrite.assertions.assertionhandler.AssertionsSimple;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.ZipUtils.ZipBuilder;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/rewrite/assertions/AssertionConfigurationAssertionHandlerNoAssertionsAfterOptimizingTest.java b/src/test/java/com/android/tools/r8/rewrite/assertions/AssertionConfigurationAssertionHandlerNoAssertionsAfterOptimizingTest.java
index 36f01a8..8e84e32 100644
--- a/src/test/java/com/android/tools/r8/rewrite/assertions/AssertionConfigurationAssertionHandlerNoAssertionsAfterOptimizingTest.java
+++ b/src/test/java/com/android/tools/r8/rewrite/assertions/AssertionConfigurationAssertionHandlerNoAssertionsAfterOptimizingTest.java
@@ -12,8 +12,8 @@
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.rewrite.assertions.assertionhandler.AssertionHandlers;
 import com.android.tools.r8.rewrite.assertions.assertionhandler.NoAssertionsAfterOptimization;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/rewrite/assertions/AssertionConfigurationAssertionHandlerRethrowingTest.java b/src/test/java/com/android/tools/r8/rewrite/assertions/AssertionConfigurationAssertionHandlerRethrowingTest.java
index c1172d8..b4fb7f7 100644
--- a/src/test/java/com/android/tools/r8/rewrite/assertions/AssertionConfigurationAssertionHandlerRethrowingTest.java
+++ b/src/test/java/com/android/tools/r8/rewrite/assertions/AssertionConfigurationAssertionHandlerRethrowingTest.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.rewrite.assertions.assertionhandler.AssertionHandlers;
 import com.android.tools.r8.rewrite.assertions.assertionhandler.AssertionsWithExceptionHandlers;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/rewrite/assertions/AssertionConfigurationAssertionHandlerSimpleTest.java b/src/test/java/com/android/tools/r8/rewrite/assertions/AssertionConfigurationAssertionHandlerSimpleTest.java
index 43e0a7e..9a4ecb9 100644
--- a/src/test/java/com/android/tools/r8/rewrite/assertions/AssertionConfigurationAssertionHandlerSimpleTest.java
+++ b/src/test/java/com/android/tools/r8/rewrite/assertions/AssertionConfigurationAssertionHandlerSimpleTest.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.rewrite.assertions.assertionhandler.AssertionHandlers;
 import com.android.tools.r8.rewrite.assertions.assertionhandler.AssertionsSimple;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/rewrite/assertions/AssertionConfigurationAssertionHandlerWithConditionsTest.java b/src/test/java/com/android/tools/r8/rewrite/assertions/AssertionConfigurationAssertionHandlerWithConditionsTest.java
index af2c8db..9194f20 100644
--- a/src/test/java/com/android/tools/r8/rewrite/assertions/AssertionConfigurationAssertionHandlerWithConditionsTest.java
+++ b/src/test/java/com/android/tools/r8/rewrite/assertions/AssertionConfigurationAssertionHandlerWithConditionsTest.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.rewrite.assertions.assertionhandler.AssertionHandlers;
 import com.android.tools.r8.rewrite.assertions.assertionhandler.AssertionsWithConditions;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/rewrite/assertions/AssertionConfigurationAssertionHandlerWithExceptionHandlersTest.java b/src/test/java/com/android/tools/r8/rewrite/assertions/AssertionConfigurationAssertionHandlerWithExceptionHandlersTest.java
index 94f47bc..26d6e28 100644
--- a/src/test/java/com/android/tools/r8/rewrite/assertions/AssertionConfigurationAssertionHandlerWithExceptionHandlersTest.java
+++ b/src/test/java/com/android/tools/r8/rewrite/assertions/AssertionConfigurationAssertionHandlerWithExceptionHandlersTest.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.rewrite.assertions.assertionhandler.AssertionHandlers;
 import com.android.tools.r8.rewrite.assertions.assertionhandler.AssertionsWithExceptionHandlers;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/rewrite/assertions/AssertionsConfigurationTest.java b/src/test/java/com/android/tools/r8/rewrite/assertions/AssertionsConfigurationTest.java
index 0c9e9e9..ad78672 100644
--- a/src/test/java/com/android/tools/r8/rewrite/assertions/AssertionsConfigurationTest.java
+++ b/src/test/java/com/android/tools/r8/rewrite/assertions/AssertionsConfigurationTest.java
@@ -17,11 +17,11 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ThrowableConsumer;
 import com.android.tools.r8.rewrite.assertions.testclasses.TestClassForInnerClass;
-import com.android.tools.r8.utils.StringUtils;
-import com.android.tools.r8.utils.internal.ThrowingConsumer;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
+import com.android.tools.r8.utils.internal.ThrowingConsumer;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Assume;
diff --git a/src/test/java/com/android/tools/r8/rewrite/assertions/RemoveAssertionsTest.java b/src/test/java/com/android/tools/r8/rewrite/assertions/RemoveAssertionsTest.java
index 04a1132..ff1e17c 100644
--- a/src/test/java/com/android/tools/r8/rewrite/assertions/RemoveAssertionsTest.java
+++ b/src/test/java/com/android/tools/r8/rewrite/assertions/RemoveAssertionsTest.java
@@ -21,10 +21,10 @@
 import com.android.tools.r8.naming.MemberNaming.MethodSignature;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.InternalOptions;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.nio.file.Path;
 import java.util.function.Function;
diff --git a/src/test/java/com/android/tools/r8/rewrite/assertions/kotlinassertionhandlerdoublecheck/AssertionConfigurationAssertionHandlerKotlinDoubleCheckTest.java b/src/test/java/com/android/tools/r8/rewrite/assertions/kotlinassertionhandlerdoublecheck/AssertionConfigurationAssertionHandlerKotlinDoubleCheckTest.java
index 32e72b6..268acc9 100644
--- a/src/test/java/com/android/tools/r8/rewrite/assertions/kotlinassertionhandlerdoublecheck/AssertionConfigurationAssertionHandlerKotlinDoubleCheckTest.java
+++ b/src/test/java/com/android/tools/r8/rewrite/assertions/kotlinassertionhandlerdoublecheck/AssertionConfigurationAssertionHandlerKotlinDoubleCheckTest.java
@@ -13,9 +13,9 @@
 import com.android.tools.r8.rewrite.assertions.AssertionConfigurationAssertionHandlerKotlinTestBase;
 import com.android.tools.r8.rewrite.assertions.assertionhandler.AssertionHandlers;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.ZipUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.nio.file.Path;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/rewrite/assertions/kotlinassertionhandlersimple/AssertionConfigurationAssertionHandlerKotlinSimpleTest.java b/src/test/java/com/android/tools/r8/rewrite/assertions/kotlinassertionhandlersimple/AssertionConfigurationAssertionHandlerKotlinSimpleTest.java
index 680620b..70f8ed3 100644
--- a/src/test/java/com/android/tools/r8/rewrite/assertions/kotlinassertionhandlersimple/AssertionConfigurationAssertionHandlerKotlinSimpleTest.java
+++ b/src/test/java/com/android/tools/r8/rewrite/assertions/kotlinassertionhandlersimple/AssertionConfigurationAssertionHandlerKotlinSimpleTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.rewrite.assertions.AssertionConfigurationAssertionHandlerKotlinTestBase;
 import com.android.tools.r8.rewrite.assertions.assertionhandler.AssertionHandlers;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.nio.file.Path;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/rewrite/assertions/kotlinassertionhandlerwithexceptions/AssertionConfigurationAssertionHandlerKotlinRethrowingTest.java b/src/test/java/com/android/tools/r8/rewrite/assertions/kotlinassertionhandlerwithexceptions/AssertionConfigurationAssertionHandlerKotlinRethrowingTest.java
index 958f53b..6dd8896 100644
--- a/src/test/java/com/android/tools/r8/rewrite/assertions/kotlinassertionhandlerwithexceptions/AssertionConfigurationAssertionHandlerKotlinRethrowingTest.java
+++ b/src/test/java/com/android/tools/r8/rewrite/assertions/kotlinassertionhandlerwithexceptions/AssertionConfigurationAssertionHandlerKotlinRethrowingTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.rewrite.assertions.AssertionConfigurationAssertionHandlerKotlinTestBase;
 import com.android.tools.r8.rewrite.assertions.assertionhandler.AssertionHandlers;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.nio.file.Path;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/rewrite/staticvalues/StaticValuesTest.java b/src/test/java/com/android/tools/r8/rewrite/staticvalues/StaticValuesTest.java
index eb4bb23..fa09d8e 100644
--- a/src/test/java/com/android/tools/r8/rewrite/staticvalues/StaticValuesTest.java
+++ b/src/test/java/com/android/tools/r8/rewrite/staticvalues/StaticValuesTest.java
@@ -16,9 +16,9 @@
 import com.android.tools.r8.smali.SmaliBuilder;
 import com.android.tools.r8.smali.SmaliTestBase;
 import com.android.tools.r8.utils.AndroidApp;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 
 public class StaticValuesTest extends SmaliTestBase {
diff --git a/src/test/java/com/android/tools/r8/rewrite/staticvalues/inlibraries/StaticLibraryValuesChangeTest.java b/src/test/java/com/android/tools/r8/rewrite/staticvalues/inlibraries/StaticLibraryValuesChangeTest.java
index 906d8e4..e541332 100644
--- a/src/test/java/com/android/tools/r8/rewrite/staticvalues/inlibraries/StaticLibraryValuesChangeTest.java
+++ b/src/test/java/com/android/tools/r8/rewrite/staticvalues/inlibraries/StaticLibraryValuesChangeTest.java
@@ -10,8 +10,8 @@
 import com.android.tools.r8.jasmin.JasminBuilder;
 import com.android.tools.r8.smali.SmaliBuilder;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.PreloadedClassFileProvider;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Path;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/rewrite/switches/MaxIntSwitchTest.java b/src/test/java/com/android/tools/r8/rewrite/switches/MaxIntSwitchTest.java
index e6a300b..172f4e2 100644
--- a/src/test/java/com/android/tools/r8/rewrite/switches/MaxIntSwitchTest.java
+++ b/src/test/java/com/android/tools/r8/rewrite/switches/MaxIntSwitchTest.java
@@ -13,11 +13,11 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import java.util.stream.Collectors;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/rewrite/switches/SwitchRewritingJarTest.java b/src/test/java/com/android/tools/r8/rewrite/switches/SwitchRewritingJarTest.java
index db1c18b..8330a79 100644
--- a/src/test/java/com/android/tools/r8/rewrite/switches/SwitchRewritingJarTest.java
+++ b/src/test/java/com/android/tools/r8/rewrite/switches/SwitchRewritingJarTest.java
@@ -11,10 +11,10 @@
 import com.android.tools.r8.jasmin.JasminBuilder;
 import com.android.tools.r8.jasmin.JasminTestBase;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.Iterator;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/rewrite/switches/SwitchRewritingTest.java b/src/test/java/com/android/tools/r8/rewrite/switches/SwitchRewritingTest.java
index 3059040..1c90622 100644
--- a/src/test/java/com/android/tools/r8/rewrite/switches/SwitchRewritingTest.java
+++ b/src/test/java/com/android/tools/r8/rewrite/switches/SwitchRewritingTest.java
@@ -23,7 +23,7 @@
 import com.android.tools.r8.smali.SmaliTestBase;
 import com.android.tools.r8.utils.AndroidApp;
 import com.android.tools.r8.utils.InternalOptions;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.function.Consumer;
 import org.junit.Test;
@@ -181,4 +181,4 @@
     // TODO(63090177): Currently this is commented out as R8 gets really slow for large switches.
     // runLargerSwitchDexTest(0, 1, Constants.U16BIT_MAX, null);
   }
-}
\ No newline at end of file
+}
diff --git a/src/test/java/com/android/tools/r8/shaking/AtomicFieldUpdaterTest.java b/src/test/java/com/android/tools/r8/shaking/AtomicFieldUpdaterTest.java
index e8146c2..f5cfaf0 100644
--- a/src/test/java/com/android/tools/r8/shaking/AtomicFieldUpdaterTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/AtomicFieldUpdaterTest.java
@@ -10,8 +10,8 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.concurrent.atomic.AtomicIntegerFieldUpdater;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/shaking/ConditionalKeepOnUsedFieldTest.java b/src/test/java/com/android/tools/r8/shaking/ConditionalKeepOnUsedFieldTest.java
index 7d8a957..41c19e0 100644
--- a/src/test/java/com/android/tools/r8/shaking/ConditionalKeepOnUsedFieldTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/ConditionalKeepOnUsedFieldTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/shaking/ConditionalKeepOnUsedMethodTest.java b/src/test/java/com/android/tools/r8/shaking/ConditionalKeepOnUsedMethodTest.java
index 8401f7b..4918202 100644
--- a/src/test/java/com/android/tools/r8/shaking/ConditionalKeepOnUsedMethodTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/ConditionalKeepOnUsedMethodTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/shaking/EventuallyNonTargetedMethodTest.java b/src/test/java/com/android/tools/r8/shaking/EventuallyNonTargetedMethodTest.java
index e31d8de..b583bb5 100644
--- a/src/test/java/com/android/tools/r8/shaking/EventuallyNonTargetedMethodTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/EventuallyNonTargetedMethodTest.java
@@ -14,9 +14,9 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/shaking/FieldTypeTest.java b/src/test/java/com/android/tools/r8/shaking/FieldTypeTest.java
index ce08a6a..72733c7 100644
--- a/src/test/java/com/android/tools/r8/shaking/FieldTypeTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/FieldTypeTest.java
@@ -18,9 +18,9 @@
 import com.android.tools.r8.naming.MemberNaming.FieldSignature;
 import com.android.tools.r8.naming.MemberNaming.MethodSignature;
 import com.android.tools.r8.utils.AndroidApp;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Path;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/shaking/FunctionTest.java b/src/test/java/com/android/tools/r8/shaking/FunctionTest.java
index a5c498a..92c30b4 100644
--- a/src/test/java/com/android/tools/r8/shaking/FunctionTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/FunctionTest.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ToolHelper.DexVm.Version;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.function.Function;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/shaking/InstantiatedLambdasTestRunner.java b/src/test/java/com/android/tools/r8/shaking/InstantiatedLambdasTestRunner.java
index 834649c..e1cc4ed 100644
--- a/src/test/java/com/android/tools/r8/shaking/InstantiatedLambdasTestRunner.java
+++ b/src/test/java/com/android/tools/r8/shaking/InstantiatedLambdasTestRunner.java
@@ -3,8 +3,6 @@
 // BSD-style license that can be found in the LICENSE file.
 package com.android.tools.r8.shaking;
 
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assume.assumeTrue;
 
 import com.android.tools.r8.ByteDataView;
 import com.android.tools.r8.ClassFileConsumer.ArchiveConsumer;
@@ -12,10 +10,8 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ToolHelper;
-import com.android.tools.r8.ToolHelper.ProcessResult;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.nio.file.Path;
 import org.junit.Before;
diff --git a/src/test/java/com/android/tools/r8/shaking/InvalidTypesTest.java b/src/test/java/com/android/tools/r8/shaking/InvalidTypesTest.java
index a7aae51..5204b34 100644
--- a/src/test/java/com/android/tools/r8/shaking/InvalidTypesTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/InvalidTypesTest.java
@@ -21,9 +21,9 @@
 import com.android.tools.r8.jasmin.JasminBuilder.ClassBuilder;
 import com.android.tools.r8.jasmin.JasminTestBase;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.UnverifiableCfCodeDiagnostic;
 import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/shaking/KeepClassMembersFieldTest.java b/src/test/java/com/android/tools/r8/shaking/KeepClassMembersFieldTest.java
index c4e838e..0f404ca 100644
--- a/src/test/java/com/android/tools/r8/shaking/KeepClassMembersFieldTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/KeepClassMembersFieldTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/shaking/LibraryProvidedProguardRulesExtractR8RulesTest.java b/src/test/java/com/android/tools/r8/shaking/LibraryProvidedProguardRulesExtractR8RulesTest.java
index 9314131..42526b8 100644
--- a/src/test/java/com/android/tools/r8/shaking/LibraryProvidedProguardRulesExtractR8RulesTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/LibraryProvidedProguardRulesExtractR8RulesTest.java
@@ -11,11 +11,11 @@
 import com.android.tools.r8.ExtractR8Rules;
 import com.android.tools.r8.ExtractR8RulesCommand;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.internal.SemanticVersion;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.ZipUtils.ZipBuilder;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.SemanticVersion;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.collections.Pair;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/shaking/LibraryProvidedProguardRulesR8SpecificTest.java b/src/test/java/com/android/tools/r8/shaking/LibraryProvidedProguardRulesR8SpecificTest.java
index 447c031..760389d 100644
--- a/src/test/java/com/android/tools/r8/shaking/LibraryProvidedProguardRulesR8SpecificTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/LibraryProvidedProguardRulesR8SpecificTest.java
@@ -13,9 +13,9 @@
 import com.android.tools.r8.Version;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.LibraryProvidedProguardRulesTestUtils;
-import com.android.tools.r8.utils.internal.SemanticVersion;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.ZipUtils.ZipBuilder;
+import com.android.tools.r8.utils.internal.SemanticVersion;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Path;
 import java.util.ArrayList;
diff --git a/src/test/java/com/android/tools/r8/shaking/LibraryProvidedProguardRulesTestBase.java b/src/test/java/com/android/tools/r8/shaking/LibraryProvidedProguardRulesTestBase.java
index dd22001..38ed6bf 100644
--- a/src/test/java/com/android/tools/r8/shaking/LibraryProvidedProguardRulesTestBase.java
+++ b/src/test/java/com/android/tools/r8/shaking/LibraryProvidedProguardRulesTestBase.java
@@ -5,8 +5,8 @@
 package com.android.tools.r8.shaking;
 
 import com.android.tools.r8.TestBase;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.ZipUtils.ZipBuilder;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.List;
 
diff --git a/src/test/java/com/android/tools/r8/shaking/NonTargetedMethodTest.java b/src/test/java/com/android/tools/r8/shaking/NonTargetedMethodTest.java
index 9290c0f..f419241 100644
--- a/src/test/java/com/android/tools/r8/shaking/NonTargetedMethodTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/NonTargetedMethodTest.java
@@ -14,9 +14,9 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/shaking/PrintConfigurationTest.java b/src/test/java/com/android/tools/r8/shaking/PrintConfigurationTest.java
index 075edcd..a138920 100644
--- a/src/test/java/com/android/tools/r8/shaking/PrintConfigurationTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/PrintConfigurationTest.java
@@ -14,8 +14,8 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime;
 import com.android.tools.r8.ToolHelper;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.base.Charsets;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/shaking/ProguardConfigurationParserTest.java b/src/test/java/com/android/tools/r8/shaking/ProguardConfigurationParserTest.java
index d9142fd..db948ae 100644
--- a/src/test/java/com/android/tools/r8/shaking/ProguardConfigurationParserTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/ProguardConfigurationParserTest.java
@@ -41,14 +41,14 @@
 import com.android.tools.r8.shaking.ProguardTypeMatcher.MatchSpecificType;
 import com.android.tools.r8.shaking.constructor.InitMatchingTest;
 import com.android.tools.r8.utils.AbortException;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.InternalOptions.PackageObfuscationMode;
 import com.android.tools.r8.utils.KeepingDiagnosticHandler;
 import com.android.tools.r8.utils.ListUtils;
 import com.android.tools.r8.utils.Reporter;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.android.tools.r8.utils.internal.IterableUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.Sets;
diff --git a/src/test/java/com/android/tools/r8/shaking/ProguardDirectoryInputsTest.java b/src/test/java/com/android/tools/r8/shaking/ProguardDirectoryInputsTest.java
index a6d9dbb..91266d6 100644
--- a/src/test/java/com/android/tools/r8/shaking/ProguardDirectoryInputsTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/ProguardDirectoryInputsTest.java
@@ -18,7 +18,7 @@
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.position.TextPosition;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.Collections;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/shaking/ReturnTypeTest.java b/src/test/java/com/android/tools/r8/shaking/ReturnTypeTest.java
index ea24ce8..b624e8e 100644
--- a/src/test/java/com/android/tools/r8/shaking/ReturnTypeTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/ReturnTypeTest.java
@@ -11,8 +11,8 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/shaking/SoftPinClassInConditionWithMethodTest.java b/src/test/java/com/android/tools/r8/shaking/SoftPinClassInConditionWithMethodTest.java
index 9f8760f..33f3775 100644
--- a/src/test/java/com/android/tools/r8/shaking/SoftPinClassInConditionWithMethodTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/SoftPinClassInConditionWithMethodTest.java
@@ -12,8 +12,8 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/shaking/SoftPinClassInConditionWithOnlyInstanceInitializerTest.java b/src/test/java/com/android/tools/r8/shaking/SoftPinClassInConditionWithOnlyInstanceInitializerTest.java
index c84c6bf..098783c 100644
--- a/src/test/java/com/android/tools/r8/shaking/SoftPinClassInConditionWithOnlyInstanceInitializerTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/SoftPinClassInConditionWithOnlyInstanceInitializerTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/shaking/TreeShakingSpecificTest.java b/src/test/java/com/android/tools/r8/shaking/TreeShakingSpecificTest.java
index 16557fc..e778254 100644
--- a/src/test/java/com/android/tools/r8/shaking/TreeShakingSpecificTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/TreeShakingSpecificTest.java
@@ -17,7 +17,7 @@
 import com.android.tools.r8.diagnostic.MissingDefinitionsDiagnostic;
 import com.android.tools.r8.mappingcompose.ComposeTestHelpers;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.nio.file.Paths;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/shaking/UsageInformationConsumerTest.java b/src/test/java/com/android/tools/r8/shaking/UsageInformationConsumerTest.java
index 42fa62f..3f837ab 100644
--- a/src/test/java/com/android/tools/r8/shaking/UsageInformationConsumerTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/UsageInformationConsumerTest.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.utils.internal.Box;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/shaking/allowshrinking/ConditionalKeepClassMethodsAllowShrinkingCompatibilityTest.java b/src/test/java/com/android/tools/r8/shaking/allowshrinking/ConditionalKeepClassMethodsAllowShrinkingCompatibilityTest.java
index cf5b0a5..a3044e7 100644
--- a/src/test/java/com/android/tools/r8/shaking/allowshrinking/ConditionalKeepClassMethodsAllowShrinkingCompatibilityTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/allowshrinking/ConditionalKeepClassMethodsAllowShrinkingCompatibilityTest.java
@@ -13,10 +13,10 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestShrinkerBuilder;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/shaking/allowshrinking/KeepAllowShrinkingCompatibilityTest.java b/src/test/java/com/android/tools/r8/shaking/allowshrinking/KeepAllowShrinkingCompatibilityTest.java
index ab66497..b5e189e 100644
--- a/src/test/java/com/android/tools/r8/shaking/allowshrinking/KeepAllowShrinkingCompatibilityTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/allowshrinking/KeepAllowShrinkingCompatibilityTest.java
@@ -13,10 +13,10 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestShrinkerBuilder;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/shaking/allowshrinking/KeepClassFieldsAllowShrinkingCompatibilityTest.java b/src/test/java/com/android/tools/r8/shaking/allowshrinking/KeepClassFieldsAllowShrinkingCompatibilityTest.java
index 03c373f..ba837db 100644
--- a/src/test/java/com/android/tools/r8/shaking/allowshrinking/KeepClassFieldsAllowShrinkingCompatibilityTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/allowshrinking/KeepClassFieldsAllowShrinkingCompatibilityTest.java
@@ -13,10 +13,10 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestShrinkerBuilder;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.FieldSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/shaking/allowshrinking/KeepClassMethodsAllowShrinkingCompatibilityTest.java b/src/test/java/com/android/tools/r8/shaking/allowshrinking/KeepClassMethodsAllowShrinkingCompatibilityTest.java
index 0c3d37c..7f0c92f 100644
--- a/src/test/java/com/android/tools/r8/shaking/allowshrinking/KeepClassMethodsAllowShrinkingCompatibilityTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/allowshrinking/KeepClassMethodsAllowShrinkingCompatibilityTest.java
@@ -13,10 +13,10 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestShrinkerBuilder;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/shaking/annotations/AnnotationsOnTargetedMethodTest.java b/src/test/java/com/android/tools/r8/shaking/annotations/AnnotationsOnTargetedMethodTest.java
index 9e77859..b8f2a98 100644
--- a/src/test/java/com/android/tools/r8/shaking/annotations/AnnotationsOnTargetedMethodTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/annotations/AnnotationsOnTargetedMethodTest.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.lang.annotation.Annotation;
 import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
diff --git a/src/test/java/com/android/tools/r8/shaking/annotations/ReflectiveAnnotationUseTest.java b/src/test/java/com/android/tools/r8/shaking/annotations/ReflectiveAnnotationUseTest.java
index d55bc17..102f7ac 100644
--- a/src/test/java/com/android/tools/r8/shaking/annotations/ReflectiveAnnotationUseTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/annotations/ReflectiveAnnotationUseTest.java
@@ -16,12 +16,12 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.graph.DexAnnotationElement;
 import com.android.tools.r8.utils.AndroidApp;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.AnnotationSubject;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.ImmutableSet;
 import java.util.Collection;
diff --git a/src/test/java/com/android/tools/r8/shaking/array/DeadArrayLengthTest.java b/src/test/java/com/android/tools/r8/shaking/array/DeadArrayLengthTest.java
index ac4e734..186e3c4 100644
--- a/src/test/java/com/android/tools/r8/shaking/array/DeadArrayLengthTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/array/DeadArrayLengthTest.java
@@ -12,11 +12,11 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/shaking/assumenosideeffects/AssumenosideeffectsPropagationTest.java b/src/test/java/com/android/tools/r8/shaking/assumenosideeffects/AssumenosideeffectsPropagationTest.java
index c98c173..5e85041 100644
--- a/src/test/java/com/android/tools/r8/shaking/assumenosideeffects/AssumenosideeffectsPropagationTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/assumenosideeffects/AssumenosideeffectsPropagationTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import java.util.Collection;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/shaking/assumenosideeffects/AssumenosideeffectsPropagationWithSuperCallTest.java b/src/test/java/com/android/tools/r8/shaking/assumenosideeffects/AssumenosideeffectsPropagationWithSuperCallTest.java
index f465c2d..d7324d7 100644
--- a/src/test/java/com/android/tools/r8/shaking/assumenosideeffects/AssumenosideeffectsPropagationWithSuperCallTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/assumenosideeffects/AssumenosideeffectsPropagationWithSuperCallTest.java
@@ -5,7 +5,7 @@
 
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import java.util.Collection;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/shaking/assumenosideeffects/AssumenosideeffectsPropagationWithoutMatchingDefinitionTest.java b/src/test/java/com/android/tools/r8/shaking/assumenosideeffects/AssumenosideeffectsPropagationWithoutMatchingDefinitionTest.java
index e041b40..3c0bba0 100644
--- a/src/test/java/com/android/tools/r8/shaking/assumenosideeffects/AssumenosideeffectsPropagationWithoutMatchingDefinitionTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/assumenosideeffects/AssumenosideeffectsPropagationWithoutMatchingDefinitionTest.java
@@ -14,10 +14,10 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/shaking/assumenosideeffects/AssumenosideeffectsVisibleMethodsTest.java b/src/test/java/com/android/tools/r8/shaking/assumenosideeffects/AssumenosideeffectsVisibleMethodsTest.java
index 421db6e..8c512f7 100644
--- a/src/test/java/com/android/tools/r8/shaking/assumenosideeffects/AssumenosideeffectsVisibleMethodsTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/assumenosideeffects/AssumenosideeffectsVisibleMethodsTest.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/shaking/assumenosideeffects/AssumenosideeffectsWithMultipleTargetsTest.java b/src/test/java/com/android/tools/r8/shaking/assumenosideeffects/AssumenosideeffectsWithMultipleTargetsTest.java
index 500543d..a7864cf 100644
--- a/src/test/java/com/android/tools/r8/shaking/assumenosideeffects/AssumenosideeffectsWithMultipleTargetsTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/assumenosideeffects/AssumenosideeffectsWithMultipleTargetsTest.java
@@ -13,11 +13,11 @@
 import com.android.tools.r8.NoVerticalClassMerging;
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FieldSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import java.util.Collection;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/shaking/assumenosideeffects/AssumenosideeffectsWithoutMatchingDefinitionTest.java b/src/test/java/com/android/tools/r8/shaking/assumenosideeffects/AssumenosideeffectsWithoutMatchingDefinitionTest.java
index b3d6af5..9f35382 100644
--- a/src/test/java/com/android/tools/r8/shaking/assumenosideeffects/AssumenosideeffectsWithoutMatchingDefinitionTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/assumenosideeffects/AssumenosideeffectsWithoutMatchingDefinitionTest.java
@@ -12,10 +12,10 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/shaking/assumenosideeffects/AssumenosideeffectsWithoutReturnValueTest.java b/src/test/java/com/android/tools/r8/shaking/assumenosideeffects/AssumenosideeffectsWithoutReturnValueTest.java
index d31b9c7..453932c 100644
--- a/src/test/java/com/android/tools/r8/shaking/assumenosideeffects/AssumenosideeffectsWithoutReturnValueTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/assumenosideeffects/AssumenosideeffectsWithoutReturnValueTest.java
@@ -11,10 +11,10 @@
 import com.android.tools.r8.NeverInline;
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import java.util.Collection;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/shaking/assumenosideeffects/StringBuildersAfterAssumenosideeffectsTest.java b/src/test/java/com/android/tools/r8/shaking/assumenosideeffects/StringBuildersAfterAssumenosideeffectsTest.java
index 659f077..3a1ac51 100644
--- a/src/test/java/com/android/tools/r8/shaking/assumenosideeffects/StringBuildersAfterAssumenosideeffectsTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/assumenosideeffects/StringBuildersAfterAssumenosideeffectsTest.java
@@ -12,10 +12,10 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/shaking/assumevalues/AssumeValuesReturnConstantStringTest.java b/src/test/java/com/android/tools/r8/shaking/assumevalues/AssumeValuesReturnConstantStringTest.java
index 84f608e..ffd7ac3 100644
--- a/src/test/java/com/android/tools/r8/shaking/assumevalues/AssumeValuesReturnConstantStringTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/assumevalues/AssumeValuesReturnConstantStringTest.java
@@ -6,7 +6,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/shaking/assumevalues/AssumevaluesWithMultipleTargetsTest.java b/src/test/java/com/android/tools/r8/shaking/assumevalues/AssumevaluesWithMultipleTargetsTest.java
index dec9b5d..460a0ff 100644
--- a/src/test/java/com/android/tools/r8/shaking/assumevalues/AssumevaluesWithMultipleTargetsTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/assumevalues/AssumevaluesWithMultipleTargetsTest.java
@@ -11,10 +11,10 @@
 import com.android.tools.r8.NeverInline;
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import java.util.Collection;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/shaking/assumevalues/DeadFieldAfterAssumevaluesTest.java b/src/test/java/com/android/tools/r8/shaking/assumevalues/DeadFieldAfterAssumevaluesTest.java
index 72567e1..af0df8a 100644
--- a/src/test/java/com/android/tools/r8/shaking/assumevalues/DeadFieldAfterAssumevaluesTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/assumevalues/DeadFieldAfterAssumevaluesTest.java
@@ -11,11 +11,11 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FieldSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/shaking/attributes/KeepExceptionsAttributeTest.java b/src/test/java/com/android/tools/r8/shaking/attributes/KeepExceptionsAttributeTest.java
index 43213c0..a767240 100644
--- a/src/test/java/com/android/tools/r8/shaking/attributes/KeepExceptionsAttributeTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/attributes/KeepExceptionsAttributeTest.java
@@ -14,9 +14,9 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/shaking/attributes/KeepInnerClassesEnclosingMethodAnnotationsTest.java b/src/test/java/com/android/tools/r8/shaking/attributes/KeepInnerClassesEnclosingMethodAnnotationsTest.java
index 70d5468..1917e96 100644
--- a/src/test/java/com/android/tools/r8/shaking/attributes/KeepInnerClassesEnclosingMethodAnnotationsTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/attributes/KeepInnerClassesEnclosingMethodAnnotationsTest.java
@@ -16,10 +16,10 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.shaking.attributes.testclasses.Outer;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/shaking/attributes/KeepSignatureTest.java b/src/test/java/com/android/tools/r8/shaking/attributes/KeepSignatureTest.java
index 57a904f..1460562 100644
--- a/src/test/java/com/android/tools/r8/shaking/attributes/KeepSignatureTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/attributes/KeepSignatureTest.java
@@ -18,12 +18,12 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FieldSubject;
 import com.android.tools.r8.utils.codeinspector.MemberSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.ArrayList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/shaking/attributes/MissingEnclosingMethodTest.java b/src/test/java/com/android/tools/r8/shaking/attributes/MissingEnclosingMethodTest.java
index c6d0a81..2323a3a 100644
--- a/src/test/java/com/android/tools/r8/shaking/attributes/MissingEnclosingMethodTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/attributes/MissingEnclosingMethodTest.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import java.io.IOException;
 import java.util.Collection;
diff --git a/src/test/java/com/android/tools/r8/shaking/constructor/ForwardingConstructorUsedFromPlatformShakingOnDexTest.java b/src/test/java/com/android/tools/r8/shaking/constructor/ForwardingConstructorUsedFromPlatformShakingOnDexTest.java
index 51ea6eb..fa6e59a 100644
--- a/src/test/java/com/android/tools/r8/shaking/constructor/ForwardingConstructorUsedFromPlatformShakingOnDexTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/constructor/ForwardingConstructorUsedFromPlatformShakingOnDexTest.java
@@ -13,9 +13,9 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.apimodel.ApiModelingTestHelper;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.BeforeClass;
diff --git a/src/test/java/com/android/tools/r8/shaking/convertchecknotnull/ConvertCheckNotNullTest.java b/src/test/java/com/android/tools/r8/shaking/convertchecknotnull/ConvertCheckNotNullTest.java
index eeb7d6c..f7aeba0 100644
--- a/src/test/java/com/android/tools/r8/shaking/convertchecknotnull/ConvertCheckNotNullTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/convertchecknotnull/ConvertCheckNotNullTest.java
@@ -16,10 +16,10 @@
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.ToolHelper.DexVm.Version;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeMatchers;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Objects;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/shaking/definitelynull/DefinitelyNullTest.java b/src/test/java/com/android/tools/r8/shaking/definitelynull/DefinitelyNullTest.java
index e762fb8..240832a 100644
--- a/src/test/java/com/android/tools/r8/shaking/definitelynull/DefinitelyNullTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/definitelynull/DefinitelyNullTest.java
@@ -7,7 +7,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ToolHelper.DexVm.Version;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.Collections;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/shaking/desugar/KeepRuleWarningTest.java b/src/test/java/com/android/tools/r8/shaking/desugar/KeepRuleWarningTest.java
index 269e3f4..e5f8961 100644
--- a/src/test/java/com/android/tools/r8/shaking/desugar/KeepRuleWarningTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/desugar/KeepRuleWarningTest.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
@@ -109,5 +109,4 @@
         .run(parameters.getRuntime(), MAIN)
         .assertSuccessWithOutput(EXPECTED_OUTPUT);
   }
-
-}
\ No newline at end of file
+}
diff --git a/src/test/java/com/android/tools/r8/shaking/desugar/dflt/DefaultMethodsTest.java b/src/test/java/com/android/tools/r8/shaking/desugar/dflt/DefaultMethodsTest.java
index 620c73d..a51c616 100644
--- a/src/test/java/com/android/tools/r8/shaking/desugar/dflt/DefaultMethodsTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/desugar/dflt/DefaultMethodsTest.java
@@ -14,9 +14,9 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.shaking.methods.MethodsTestBase.Shrinker;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 import java.util.Collection;
diff --git a/src/test/java/com/android/tools/r8/shaking/enums/EnumArrayInAnnotationTest.java b/src/test/java/com/android/tools/r8/shaking/enums/EnumArrayInAnnotationTest.java
index 5c5c80f..15376cb 100644
--- a/src/test/java/com/android/tools/r8/shaking/enums/EnumArrayInAnnotationTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/enums/EnumArrayInAnnotationTest.java
@@ -19,7 +19,7 @@
 import com.android.tools.r8.TestState;
 import com.android.tools.r8.utils.internal.BooleanUtils;
 import com.android.tools.r8.utils.internal.Box;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
diff --git a/src/test/java/com/android/tools/r8/shaking/enums/EnumInAnnotationTest.java b/src/test/java/com/android/tools/r8/shaking/enums/EnumInAnnotationTest.java
index b26cd9b..5e3e75c 100644
--- a/src/test/java/com/android/tools/r8/shaking/enums/EnumInAnnotationTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/enums/EnumInAnnotationTest.java
@@ -18,7 +18,7 @@
 import com.android.tools.r8.TestState;
 import com.android.tools.r8.utils.internal.BooleanUtils;
 import com.android.tools.r8.utils.internal.Box;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
diff --git a/src/test/java/com/android/tools/r8/shaking/enums/EnumInAnnotationWhereAnnotationIsDeadTest.java b/src/test/java/com/android/tools/r8/shaking/enums/EnumInAnnotationWhereAnnotationIsDeadTest.java
index 815484d..0a9680c 100644
--- a/src/test/java/com/android/tools/r8/shaking/enums/EnumInAnnotationWhereAnnotationIsDeadTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/enums/EnumInAnnotationWhereAnnotationIsDeadTest.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
diff --git a/src/test/java/com/android/tools/r8/shaking/enums/IsEnumRemovalTest.java b/src/test/java/com/android/tools/r8/shaking/enums/IsEnumRemovalTest.java
index 669498a..8097f2e 100644
--- a/src/test/java/com/android/tools/r8/shaking/enums/IsEnumRemovalTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/enums/IsEnumRemovalTest.java
@@ -10,9 +10,9 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Set;
 import org.junit.Assert;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumenosideeffects1Test.java b/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumenosideeffects1Test.java
index 42c3096..a17305b 100644
--- a/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumenosideeffects1Test.java
+++ b/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumenosideeffects1Test.java
@@ -5,7 +5,7 @@
 
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.shaking.TreeShakingTest;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Assert;
diff --git a/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumenosideeffects2Test.java b/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumenosideeffects2Test.java
index cb141fb..da1911a 100644
--- a/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumenosideeffects2Test.java
+++ b/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumenosideeffects2Test.java
@@ -5,7 +5,7 @@
 
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.shaking.TreeShakingTest;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Assert;
diff --git a/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumenosideeffects3Test.java b/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumenosideeffects3Test.java
index ac17be8..ef9e0b2 100644
--- a/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumenosideeffects3Test.java
+++ b/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumenosideeffects3Test.java
@@ -5,7 +5,7 @@
 
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.shaking.TreeShakingTest;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Assert;
diff --git a/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumenosideeffects4Test.java b/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumenosideeffects4Test.java
index 4b5a370..d07bcf4 100644
--- a/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumenosideeffects4Test.java
+++ b/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumenosideeffects4Test.java
@@ -5,7 +5,7 @@
 
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.shaking.TreeShakingTest;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Assert;
diff --git a/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumenosideeffects5Test.java b/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumenosideeffects5Test.java
index 6fe0e05..cab43ed 100644
--- a/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumenosideeffects5Test.java
+++ b/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumenosideeffects5Test.java
@@ -5,7 +5,7 @@
 
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.shaking.TreeShakingTest;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Assert;
diff --git a/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumenosideeffects6Test.java b/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumenosideeffects6Test.java
index 1948663..16b1cd6 100644
--- a/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumenosideeffects6Test.java
+++ b/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumenosideeffects6Test.java
@@ -5,7 +5,7 @@
 
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.shaking.TreeShakingTest;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Assert;
diff --git a/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumevalues1Test.java b/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumevalues1Test.java
index ac1338c..d8510077 100644
--- a/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumevalues1Test.java
+++ b/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumevalues1Test.java
@@ -5,7 +5,7 @@
 
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.shaking.TreeShakingTest;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Assert;
diff --git a/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumevalues2Test.java b/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumevalues2Test.java
index 2dd0cc6..c4096e0 100644
--- a/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumevalues2Test.java
+++ b/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumevalues2Test.java
@@ -5,7 +5,7 @@
 
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.shaking.TreeShakingTest;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Assert;
diff --git a/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumevalues3Test.java b/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumevalues3Test.java
index f80b2f8..6c4cb96 100644
--- a/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumevalues3Test.java
+++ b/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumevalues3Test.java
@@ -5,7 +5,7 @@
 
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.shaking.TreeShakingTest;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Assert;
diff --git a/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumevalues4Test.java b/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumevalues4Test.java
index 6b1d691..bb8062d 100644
--- a/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumevalues4Test.java
+++ b/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumevalues4Test.java
@@ -5,7 +5,7 @@
 
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.shaking.TreeShakingTest;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Assert;
diff --git a/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumevalues5Test.java b/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumevalues5Test.java
index 8ee9a97..e6bf110 100644
--- a/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumevalues5Test.java
+++ b/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumevalues5Test.java
@@ -5,7 +5,7 @@
 
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.shaking.TreeShakingTest;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Assert;
diff --git a/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumevalues6Test.java b/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumevalues6Test.java
index 882a3e4..8532f93 100644
--- a/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumevalues6Test.java
+++ b/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumevalues6Test.java
@@ -5,10 +5,10 @@
 
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.shaking.TreeShakingTest;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.ConstStringInstructionSubject;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject.JumboStringMode;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Assert;
@@ -70,4 +70,4 @@
     Assert.assertEquals(expected, output1);
     Assert.assertEquals(expected, output2);
   }
-}
\ No newline at end of file
+}
diff --git a/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumevalues7Test.java b/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumevalues7Test.java
index f61dbd7..c4d4883 100644
--- a/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumevalues7Test.java
+++ b/src/test/java/com/android/tools/r8/shaking/examples/TreeShakingAssumevalues7Test.java
@@ -5,10 +5,10 @@
 
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.shaking.TreeShakingTest;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.ConstStringInstructionSubject;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject.JumboStringMode;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Assert;
@@ -69,4 +69,4 @@
     Assert.assertEquals(StringUtils.lines("NOPE_STATIC_NOT_NULL", "NOPE_NOT_NULL", "OK"), output1);
     Assert.assertEquals(StringUtils.lines("OK"), output2);
   }
-}
\ No newline at end of file
+}
diff --git a/src/test/java/com/android/tools/r8/shaking/fields/FieldsTestBase.java b/src/test/java/com/android/tools/r8/shaking/fields/FieldsTestBase.java
index db454c22..492f531 100644
--- a/src/test/java/com/android/tools/r8/shaking/fields/FieldsTestBase.java
+++ b/src/test/java/com/android/tools/r8/shaking/fields/FieldsTestBase.java
@@ -6,9 +6,9 @@
 
 import com.android.tools.r8.NoVerticalClassMerging;
 import com.android.tools.r8.TestBase;
-import com.android.tools.r8.utils.StringUtils;
-import com.android.tools.r8.utils.internal.ThrowingConsumer;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
+import com.android.tools.r8.utils.internal.ThrowingConsumer;
 import com.google.common.collect.ImmutableList;
 import java.util.Collection;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/shaking/fields/shadow/ShadowFieldsTest.java b/src/test/java/com/android/tools/r8/shaking/fields/shadow/ShadowFieldsTest.java
index da756b3..cb434b2 100644
--- a/src/test/java/com/android/tools/r8/shaking/fields/shadow/ShadowFieldsTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/fields/shadow/ShadowFieldsTest.java
@@ -9,9 +9,9 @@
 
 import com.android.tools.r8.NoVerticalClassMerging;
 import com.android.tools.r8.shaking.fields.FieldsTestBase;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableSet;
 import java.util.Collection;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/shaking/forceproguardcompatibility/defaultctor/KeepClassMembersDefaultCtorTest.java b/src/test/java/com/android/tools/r8/shaking/forceproguardcompatibility/defaultctor/KeepClassMembersDefaultCtorTest.java
index 1870c7e..f27edaf 100644
--- a/src/test/java/com/android/tools/r8/shaking/forceproguardcompatibility/defaultctor/KeepClassMembersDefaultCtorTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/forceproguardcompatibility/defaultctor/KeepClassMembersDefaultCtorTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRunResult;
 import com.android.tools.r8.TestShrinkerBuilder;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/shaking/forceproguardcompatibility/defaultctor/KeepClassesWithMembersDefaultCtorTest.java b/src/test/java/com/android/tools/r8/shaking/forceproguardcompatibility/defaultctor/KeepClassesWithMembersDefaultCtorTest.java
index 54ee56f..9423d4b 100644
--- a/src/test/java/com/android/tools/r8/shaking/forceproguardcompatibility/defaultctor/KeepClassesWithMembersDefaultCtorTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/forceproguardcompatibility/defaultctor/KeepClassesWithMembersDefaultCtorTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRunResult;
 import com.android.tools.r8.TestShrinkerBuilder;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/shaking/forceproguardcompatibility/keepinterface/CompatKeepInterfaceAsInstantiatedTest.java b/src/test/java/com/android/tools/r8/shaking/forceproguardcompatibility/keepinterface/CompatKeepInterfaceAsInstantiatedTest.java
index d931285..d349a49 100644
--- a/src/test/java/com/android/tools/r8/shaking/forceproguardcompatibility/keepinterface/CompatKeepInterfaceAsInstantiatedTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/forceproguardcompatibility/keepinterface/CompatKeepInterfaceAsInstantiatedTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRunResult;
 import com.android.tools.r8.TestShrinkerBuilder;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/shaking/ifrule/ConditionalKeepClassWithMembersTest.java b/src/test/java/com/android/tools/r8/shaking/ifrule/ConditionalKeepClassWithMembersTest.java
index b719464..b724a23 100644
--- a/src/test/java/com/android/tools/r8/shaking/ifrule/ConditionalKeepClassWithMembersTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/ifrule/ConditionalKeepClassWithMembersTest.java
@@ -11,8 +11,8 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/shaking/ifrule/ConditionalKeepIfKeptTest.java b/src/test/java/com/android/tools/r8/shaking/ifrule/ConditionalKeepIfKeptTest.java
index 1e65664..4130d7f 100644
--- a/src/test/java/com/android/tools/r8/shaking/ifrule/ConditionalKeepIfKeptTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/ifrule/ConditionalKeepIfKeptTest.java
@@ -11,9 +11,9 @@
 
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Assume;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/shaking/ifrule/IfOnTargetedMethodTest.java b/src/test/java/com/android/tools/r8/shaking/ifrule/IfOnTargetedMethodTest.java
index f5aba70..8452c2a 100644
--- a/src/test/java/com/android/tools/r8/shaking/ifrule/IfOnTargetedMethodTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/ifrule/IfOnTargetedMethodTest.java
@@ -11,9 +11,9 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.lang.reflect.Proxy;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/shaking/ifrule/StaticFinalFieldInliningTest.java b/src/test/java/com/android/tools/r8/shaking/ifrule/StaticFinalFieldInliningTest.java
index 5f7d1f8..d219fb4 100644
--- a/src/test/java/com/android/tools/r8/shaking/ifrule/StaticFinalFieldInliningTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/ifrule/StaticFinalFieldInliningTest.java
@@ -17,10 +17,10 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.errors.InlinableStaticFinalFieldPreconditionDiagnostic;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/shaking/ifrule/applymapping/IfRuleWithApplyMappingTest.java b/src/test/java/com/android/tools/r8/shaking/ifrule/applymapping/IfRuleWithApplyMappingTest.java
index c74b2b1..da02909 100644
--- a/src/test/java/com/android/tools/r8/shaking/ifrule/applymapping/IfRuleWithApplyMappingTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/ifrule/applymapping/IfRuleWithApplyMappingTest.java
@@ -9,9 +9,9 @@
 import static org.junit.Assert.assertEquals;
 
 import com.android.tools.r8.TestBase;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.FileUtils;
 import java.nio.file.Path;
 import org.junit.Before;
 import org.junit.Ignore;
diff --git a/src/test/java/com/android/tools/r8/shaking/ifrule/classinlining/IfRuleWithClassInlining.java b/src/test/java/com/android/tools/r8/shaking/ifrule/classinlining/IfRuleWithClassInlining.java
index 040898d..38a23e9 100644
--- a/src/test/java/com/android/tools/r8/shaking/ifrule/classinlining/IfRuleWithClassInlining.java
+++ b/src/test/java/com/android/tools/r8/shaking/ifrule/classinlining/IfRuleWithClassInlining.java
@@ -12,9 +12,9 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/shaking/ifrule/classstaticizer/IfRuleWithClassStaticizerTest.java b/src/test/java/com/android/tools/r8/shaking/ifrule/classstaticizer/IfRuleWithClassStaticizerTest.java
index eaf5faa..9e462e1 100644
--- a/src/test/java/com/android/tools/r8/shaking/ifrule/classstaticizer/IfRuleWithClassStaticizerTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/ifrule/classstaticizer/IfRuleWithClassStaticizerTest.java
@@ -15,10 +15,10 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.shaking.ifrule.classstaticizer.IfRuleWithClassStaticizerTest.StaticizerCandidate.Companion;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FoundMethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import java.util.stream.Collectors;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/shaking/ifrule/interfacemethoddesugaring/IfRuleWithInterfaceMethodDesugaringTest.java b/src/test/java/com/android/tools/r8/shaking/ifrule/interfacemethoddesugaring/IfRuleWithInterfaceMethodDesugaringTest.java
index 86d1074..39503ea 100644
--- a/src/test/java/com/android/tools/r8/shaking/ifrule/interfacemethoddesugaring/IfRuleWithInterfaceMethodDesugaringTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/ifrule/interfacemethoddesugaring/IfRuleWithInterfaceMethodDesugaringTest.java
@@ -20,10 +20,10 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/shaking/ifrule/verticalclassmerging/IfRuleWithVerticalClassMerging.java b/src/test/java/com/android/tools/r8/shaking/ifrule/verticalclassmerging/IfRuleWithVerticalClassMerging.java
index 54206ab..ffabd92 100644
--- a/src/test/java/com/android/tools/r8/shaking/ifrule/verticalclassmerging/IfRuleWithVerticalClassMerging.java
+++ b/src/test/java/com/android/tools/r8/shaking/ifrule/verticalclassmerging/IfRuleWithVerticalClassMerging.java
@@ -11,11 +11,11 @@
 import com.android.tools.r8.NeverClassInline;
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.internal.BooleanUtils;
 import com.android.tools.r8.utils.InternalOptions;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.Collection;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/shaking/keepparameternames/KeepParameterNamesTest.java b/src/test/java/com/android/tools/r8/shaking/keepparameternames/KeepParameterNamesTest.java
index 29466a0..5a83bba 100644
--- a/src/test/java/com/android/tools/r8/shaking/keepparameternames/KeepParameterNamesTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/keepparameternames/KeepParameterNamesTest.java
@@ -17,14 +17,14 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestShrinkerBuilder;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.LocalVariableTable;
 import com.android.tools.r8.utils.codeinspector.LocalVariableTable.LocalVariableTableEntry;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
 import com.android.tools.r8.utils.codeinspector.TypeSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Collection;
 import java.util.List;
 import java.util.Map;
diff --git a/src/test/java/com/android/tools/r8/shaking/keepparameternames/KeepParameterNamesUnsortedLocalVariablesTableTest.java b/src/test/java/com/android/tools/r8/shaking/keepparameternames/KeepParameterNamesUnsortedLocalVariablesTableTest.java
index 3c54557..8ebd925 100644
--- a/src/test/java/com/android/tools/r8/shaking/keepparameternames/KeepParameterNamesUnsortedLocalVariablesTableTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/keepparameternames/KeepParameterNamesUnsortedLocalVariablesTableTest.java
@@ -11,14 +11,14 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestShrinkerBuilder;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.LocalVariableTable;
 import com.android.tools.r8.utils.codeinspector.LocalVariableTable.LocalVariableTableEntry;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
 import com.android.tools.r8.utils.codeinspector.TypeSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.lang.reflect.Method;
 import java.util.Collection;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByAnnotatedClassTestRunner.java b/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByAnnotatedClassTestRunner.java
index 053ec70..8bab357 100644
--- a/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByAnnotatedClassTestRunner.java
+++ b/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByAnnotatedClassTestRunner.java
@@ -11,9 +11,9 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.references.MethodReference;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.graphinspector.GraphInspector;
 import com.android.tools.r8.utils.graphinspector.GraphInspector.QueryNode;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByAnnotatedMethodTestRunner.java b/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByAnnotatedMethodTestRunner.java
index d4825c1..2f7e272 100644
--- a/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByAnnotatedMethodTestRunner.java
+++ b/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByAnnotatedMethodTestRunner.java
@@ -12,9 +12,9 @@
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.references.MethodReference;
 import com.android.tools.r8.references.Reference;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.graphinspector.GraphInspector;
 import com.android.tools.r8.utils.graphinspector.GraphInspector.QueryNode;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.Collection;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByConditionalOnMethodTest.java b/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByConditionalOnMethodTest.java
index 235de24..f4e2a03 100644
--- a/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByConditionalOnMethodTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByConditionalOnMethodTest.java
@@ -13,9 +13,9 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.references.MethodReference;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.graphinspector.GraphInspector;
 import com.android.tools.r8.utils.graphinspector.GraphInspector.QueryNode;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByConditionalRuleTestRunner.java b/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByConditionalRuleTestRunner.java
index 4964ba5..d21f7fc 100644
--- a/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByConditionalRuleTestRunner.java
+++ b/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByConditionalRuleTestRunner.java
@@ -15,10 +15,10 @@
 import com.android.tools.r8.references.ClassReference;
 import com.android.tools.r8.references.MethodReference;
 import com.android.tools.r8.shaking.WhyAreYouKeepingConsumer;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.graphinspector.GraphInspector;
 import com.android.tools.r8.utils.graphinspector.GraphInspector.QueryNode;
 import com.android.tools.r8.utils.graphinspector.GraphInspector.QueryNodeSet;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.ByteArrayOutputStream;
 import java.io.PrintStream;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByFieldReflectionTestRunner.java b/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByFieldReflectionTestRunner.java
index 12bfedb..572adbc 100644
--- a/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByFieldReflectionTestRunner.java
+++ b/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByFieldReflectionTestRunner.java
@@ -14,9 +14,9 @@
 import com.android.tools.r8.references.FieldReference;
 import com.android.tools.r8.references.MethodReference;
 import com.android.tools.r8.shaking.WhyAreYouKeepingConsumer;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.graphinspector.GraphInspector;
 import com.android.tools.r8.utils.graphinspector.GraphInspector.QueryNode;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.ByteArrayOutputStream;
 import java.io.PrintStream;
 import java.util.Arrays;
diff --git a/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByKeepClassMembersNonStaticTestRunner.java b/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByKeepClassMembersNonStaticTestRunner.java
index dc87e2d..4096e33 100644
--- a/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByKeepClassMembersNonStaticTestRunner.java
+++ b/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByKeepClassMembersNonStaticTestRunner.java
@@ -17,9 +17,9 @@
 import com.android.tools.r8.references.ClassReference;
 import com.android.tools.r8.references.MethodReference;
 import com.android.tools.r8.shaking.WhyAreYouKeepingConsumer;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.graphinspector.GraphInspector;
 import com.android.tools.r8.utils.graphinspector.GraphInspector.QueryNode;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.ByteArrayOutputStream;
 import java.io.PrintStream;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByKeepClassMembersTestRunner.java b/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByKeepClassMembersTestRunner.java
index 68f3a5d..27d28e8 100644
--- a/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByKeepClassMembersTestRunner.java
+++ b/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByKeepClassMembersTestRunner.java
@@ -14,9 +14,9 @@
 import com.android.tools.r8.references.ClassReference;
 import com.android.tools.r8.references.MethodReference;
 import com.android.tools.r8.shaking.WhyAreYouKeepingConsumer;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.graphinspector.GraphInspector;
 import com.android.tools.r8.utils.graphinspector.GraphInspector.QueryNode;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.ByteArrayOutputStream;
 import java.io.PrintStream;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByMethodReflectionTestRunner.java b/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByMethodReflectionTestRunner.java
index 28ab3d8..542c449 100644
--- a/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByMethodReflectionTestRunner.java
+++ b/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByMethodReflectionTestRunner.java
@@ -12,9 +12,9 @@
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.references.MethodReference;
 import com.android.tools.r8.shaking.WhyAreYouKeepingConsumer;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.graphinspector.GraphInspector;
 import com.android.tools.r8.utils.graphinspector.GraphInspector.QueryNode;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.ByteArrayOutputStream;
 import java.io.PrintStream;
 import java.util.Arrays;
diff --git a/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByReachableSubclassTest.java b/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByReachableSubclassTest.java
index ae37674..f57c2cd 100644
--- a/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByReachableSubclassTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByReachableSubclassTest.java
@@ -14,9 +14,9 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.references.Reference;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.graphinspector.GraphInspector;
 import com.android.tools.r8.utils.graphinspector.GraphInspector.QueryNode;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByTwoMethods.java b/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByTwoMethods.java
index c238e5d..49798b9 100644
--- a/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByTwoMethods.java
+++ b/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByTwoMethods.java
@@ -13,9 +13,9 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.references.MethodReference;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.graphinspector.GraphInspector;
 import com.android.tools.r8.utils.graphinspector.GraphInspector.QueryNode;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByTwoRulesTestRunner.java b/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByTwoRulesTestRunner.java
index 66aef0f..7c13e54 100644
--- a/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByTwoRulesTestRunner.java
+++ b/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptByTwoRulesTestRunner.java
@@ -11,9 +11,9 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.references.MethodReference;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.graphinspector.GraphInspector;
 import com.android.tools.r8.utils.graphinspector.GraphInspector.QueryNode;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.Collection;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptMethodTestRunner.java b/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptMethodTestRunner.java
index 8d0efbad..6841d39 100644
--- a/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptMethodTestRunner.java
+++ b/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptMethodTestRunner.java
@@ -11,9 +11,9 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.references.MethodReference;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.graphinspector.GraphInspector;
 import com.android.tools.r8.utils.graphinspector.GraphInspector.QueryNode;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptSingletonIsNotCyclicTest.java b/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptSingletonIsNotCyclicTest.java
index b012f3d..5208b8b 100644
--- a/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptSingletonIsNotCyclicTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptSingletonIsNotCyclicTest.java
@@ -21,9 +21,9 @@
 import com.android.tools.r8.references.MethodReference;
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.shaking.WhyAreYouKeepingConsumer;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.graphinspector.GraphInspector;
 import com.android.tools.r8.utils.graphinspector.GraphInspector.QueryNode;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.ByteArrayOutputStream;
 import java.io.PrintStream;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptSubclassKeepsSuperTest.java b/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptSubclassKeepsSuperTest.java
index cd34b55..af5ed9b 100644
--- a/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptSubclassKeepsSuperTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptSubclassKeepsSuperTest.java
@@ -14,9 +14,9 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.references.Reference;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.graphinspector.GraphInspector;
 import com.android.tools.r8.utils.graphinspector.GraphInspector.QueryNode;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptViaClassInitializerTestRunner.java b/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptViaClassInitializerTestRunner.java
index 221f99c..dffc9b5 100644
--- a/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptViaClassInitializerTestRunner.java
+++ b/src/test/java/com/android/tools/r8/shaking/keptgraph/KeptViaClassInitializerTestRunner.java
@@ -23,9 +23,9 @@
 import com.android.tools.r8.shaking.WhyAreYouKeepingConsumer;
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.graphinspector.GraphInspector;
 import com.android.tools.r8.utils.graphinspector.GraphInspector.QueryNode;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.ByteArrayOutputStream;
 import java.io.PrintStream;
 import java.util.function.Supplier;
diff --git a/src/test/java/com/android/tools/r8/shaking/keptgraph/RemovedClassTestRunner.java b/src/test/java/com/android/tools/r8/shaking/keptgraph/RemovedClassTestRunner.java
index 49877df..8cc69ca 100644
--- a/src/test/java/com/android/tools/r8/shaking/keptgraph/RemovedClassTestRunner.java
+++ b/src/test/java/com/android/tools/r8/shaking/keptgraph/RemovedClassTestRunner.java
@@ -14,9 +14,9 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.references.MethodReference;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.graphinspector.GraphInspector;
 import com.android.tools.r8.utils.graphinspector.GraphInspector.QueryNode;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/shaking/methods/MethodsTestBase.java b/src/test/java/com/android/tools/r8/shaking/methods/MethodsTestBase.java
index 117caa4..eeeda58 100644
--- a/src/test/java/com/android/tools/r8/shaking/methods/MethodsTestBase.java
+++ b/src/test/java/com/android/tools/r8/shaking/methods/MethodsTestBase.java
@@ -8,8 +8,8 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.Collection;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/shaking/methods/abst/AbstractMethodsTest.java b/src/test/java/com/android/tools/r8/shaking/methods/abst/AbstractMethodsTest.java
index 438355c..a2d0156 100644
--- a/src/test/java/com/android/tools/r8/shaking/methods/abst/AbstractMethodsTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/methods/abst/AbstractMethodsTest.java
@@ -11,10 +11,10 @@
 
 import com.android.tools.r8.NoVerticalClassMerging;
 import com.android.tools.r8.shaking.methods.MethodsTestBase;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableSet;
 import java.util.Collection;
 import java.util.Set;
diff --git a/src/test/java/com/android/tools/r8/shaking/methods/interfaces/MultipleRulesRegression228791247Test.java b/src/test/java/com/android/tools/r8/shaking/methods/interfaces/MultipleRulesRegression228791247Test.java
index 3c319fa..5d98a8b 100644
--- a/src/test/java/com/android/tools/r8/shaking/methods/interfaces/MultipleRulesRegression228791247Test.java
+++ b/src/test/java/com/android/tools/r8/shaking/methods/interfaces/MultipleRulesRegression228791247Test.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/shaking/methods/prvt/PrivateMethodsTest.java b/src/test/java/com/android/tools/r8/shaking/methods/prvt/PrivateMethodsTest.java
index 9bd8465..80d4900 100644
--- a/src/test/java/com/android/tools/r8/shaking/methods/prvt/PrivateMethodsTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/methods/prvt/PrivateMethodsTest.java
@@ -10,9 +10,9 @@
 
 import com.android.tools.r8.NoVerticalClassMerging;
 import com.android.tools.r8.shaking.methods.MethodsTestBase;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableSet;
 import java.util.Collection;
 import java.util.Set;
diff --git a/src/test/java/com/android/tools/r8/shaking/methods/shadow/ShadowMethodsTest.java b/src/test/java/com/android/tools/r8/shaking/methods/shadow/ShadowMethodsTest.java
index 94f4646..b05674b 100644
--- a/src/test/java/com/android/tools/r8/shaking/methods/shadow/ShadowMethodsTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/methods/shadow/ShadowMethodsTest.java
@@ -10,9 +10,9 @@
 
 import com.android.tools.r8.NoVerticalClassMerging;
 import com.android.tools.r8.shaking.methods.MethodsTestBase;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableSet;
 import java.util.Collection;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/shaking/modifiers/AccessFlagsCombinationsTest.java b/src/test/java/com/android/tools/r8/shaking/modifiers/AccessFlagsCombinationsTest.java
index e47c9a5..239c300 100644
--- a/src/test/java/com/android/tools/r8/shaking/modifiers/AccessFlagsCombinationsTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/modifiers/AccessFlagsCombinationsTest.java
@@ -10,10 +10,10 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.dex.Constants;
-import com.android.tools.r8.utils.StringUtils;
-import com.android.tools.r8.utils.internal.ThrowingConsumer;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
+import com.android.tools.r8.utils.internal.ThrowingConsumer;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/shaking/negatedrules/NegatedMethodArgumentTest.java b/src/test/java/com/android/tools/r8/shaking/negatedrules/NegatedMethodArgumentTest.java
index a7c8fb3..bd12e39 100644
--- a/src/test/java/com/android/tools/r8/shaking/negatedrules/NegatedMethodArgumentTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/negatedrules/NegatedMethodArgumentTest.java
@@ -15,9 +15,9 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.FoundMethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/shaking/proxy/MockitoTest.java b/src/test/java/com/android/tools/r8/shaking/proxy/MockitoTest.java
index e0bacad..728e7f8 100644
--- a/src/test/java/com/android/tools/r8/shaking/proxy/MockitoTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/proxy/MockitoTest.java
@@ -11,11 +11,11 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.ToolHelper;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import java.nio.file.Path;
 import java.nio.file.Paths;
 import java.util.Collection;
diff --git a/src/test/java/com/android/tools/r8/shaking/proxy/ProxiesTest.java b/src/test/java/com/android/tools/r8/shaking/proxy/ProxiesTest.java
index f8db087..a52d7d7 100644
--- a/src/test/java/com/android/tools/r8/shaking/proxy/ProxiesTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/proxy/ProxiesTest.java
@@ -16,13 +16,13 @@
 import com.android.tools.r8.shaking.proxy.testclasses.SubClass;
 import com.android.tools.r8.shaking.proxy.testclasses.SubInterface;
 import com.android.tools.r8.shaking.proxy.testclasses.TestClass;
-import com.android.tools.r8.utils.StringUtils;
-import com.android.tools.r8.utils.internal.ThrowingConsumer;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FoundMethodSubject;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.InvokeInstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
+import com.android.tools.r8.utils.internal.ThrowingConsumer;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Streams;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/shaking/reflection/ReflectiveNewInstanceTest.java b/src/test/java/com/android/tools/r8/shaking/reflection/ReflectiveNewInstanceTest.java
index 8920a35..af382bd 100644
--- a/src/test/java/com/android/tools/r8/shaking/reflection/ReflectiveNewInstanceTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/reflection/ReflectiveNewInstanceTest.java
@@ -12,9 +12,9 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.references.MethodReference;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.graphinspector.GraphInspector;
 import com.android.tools.r8.utils.graphinspector.GraphInspector.QueryNode;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.lang.reflect.Constructor;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/shaking/whyareyoukeeping/WhyAreYouKeepingIgnoreAllowShrinkingRulesTest.java b/src/test/java/com/android/tools/r8/shaking/whyareyoukeeping/WhyAreYouKeepingIgnoreAllowShrinkingRulesTest.java
index 7704a84..7c22941 100644
--- a/src/test/java/com/android/tools/r8/shaking/whyareyoukeeping/WhyAreYouKeepingIgnoreAllowShrinkingRulesTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/whyareyoukeeping/WhyAreYouKeepingIgnoreAllowShrinkingRulesTest.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java/com/android/tools/r8/shaking/whyareyoukeeping/WhyAreYouKeepingTest.java b/src/test/java/com/android/tools/r8/shaking/whyareyoukeeping/WhyAreYouKeepingTest.java
index 477e1f3..4a7a965 100644
--- a/src/test/java/com/android/tools/r8/shaking/whyareyoukeeping/WhyAreYouKeepingTest.java
+++ b/src/test/java/com/android/tools/r8/shaking/whyareyoukeeping/WhyAreYouKeepingTest.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.shaking.WhyAreYouKeepingConsumer;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.ByteArrayOutputStream;
 import java.io.PrintStream;
 import java.nio.charset.StandardCharsets;
diff --git a/src/test/java/com/android/tools/r8/smali/DexMoveInstructionsTest.java b/src/test/java/com/android/tools/r8/smali/DexMoveInstructionsTest.java
index 677d57a..6530cc4 100644
--- a/src/test/java/com/android/tools/r8/smali/DexMoveInstructionsTest.java
+++ b/src/test/java/com/android/tools/r8/smali/DexMoveInstructionsTest.java
@@ -9,7 +9,7 @@
 
 import com.android.tools.r8.ToolHelper.ProcessResult;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
diff --git a/src/test/java/com/android/tools/r8/smali/IfZeroObjectTest.java b/src/test/java/com/android/tools/r8/smali/IfZeroObjectTest.java
index 6211aec..d0778e2 100644
--- a/src/test/java/com/android/tools/r8/smali/IfZeroObjectTest.java
+++ b/src/test/java/com/android/tools/r8/smali/IfZeroObjectTest.java
@@ -8,7 +8,7 @@
 import static org.junit.Assert.assertTrue;
 
 import com.android.tools.r8.ToolHelper.ProcessResult;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
diff --git a/src/test/java/com/android/tools/r8/smali/JumboStringTest.java b/src/test/java/com/android/tools/r8/smali/JumboStringTest.java
index 623ef25..9933b3d 100644
--- a/src/test/java/com/android/tools/r8/smali/JumboStringTest.java
+++ b/src/test/java/com/android/tools/r8/smali/JumboStringTest.java
@@ -10,10 +10,10 @@
 
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.collections.Pair;
 import com.google.common.collect.ImmutableList;
 import org.junit.BeforeClass;
diff --git a/src/test/java/com/android/tools/r8/smali/OutlineTest.java b/src/test/java/com/android/tools/r8/smali/OutlineTest.java
index 9eeb128..e4749b1 100644
--- a/src/test/java/com/android/tools/r8/smali/OutlineTest.java
+++ b/src/test/java/com/android/tools/r8/smali/OutlineTest.java
@@ -40,9 +40,9 @@
 import com.android.tools.r8.utils.AndroidApp;
 import com.android.tools.r8.utils.InternalOptions;
 import com.android.tools.r8.utils.InternalOptions.OutlineOptions;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FoundClassSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.ArrayList;
 import java.util.Arrays;
diff --git a/src/test/java/com/android/tools/r8/smali/Regress38014736.java b/src/test/java/com/android/tools/r8/smali/Regress38014736.java
index 1f0cd78..15a7192 100644
--- a/src/test/java/com/android/tools/r8/smali/Regress38014736.java
+++ b/src/test/java/com/android/tools/r8/smali/Regress38014736.java
@@ -6,7 +6,7 @@
 import static org.junit.Assert.assertTrue;
 
 import com.android.tools.r8.utils.AndroidApp;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 
 public class Regress38014736 extends SmaliTestBase {
diff --git a/src/test/java/com/android/tools/r8/smali/RunArtSmokeTest.java b/src/test/java/com/android/tools/r8/smali/RunArtSmokeTest.java
index 00e8d8f..3fdd598 100644
--- a/src/test/java/com/android/tools/r8/smali/RunArtSmokeTest.java
+++ b/src/test/java/com/android/tools/r8/smali/RunArtSmokeTest.java
@@ -16,7 +16,7 @@
 import com.android.tools.r8.graph.DexEncodedMethod;
 import com.android.tools.r8.smali.SmaliBuilder.MethodSignature;
 import com.android.tools.r8.utils.AndroidApp;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 
 public class RunArtSmokeTest extends SmaliTestBase {
diff --git a/src/test/java/com/android/tools/r8/startup/GenerateInstrumentationServerClassesTest.java b/src/test/java/com/android/tools/r8/startup/GenerateInstrumentationServerClassesTest.java
index 8238492..fdb2991 100644
--- a/src/test/java/com/android/tools/r8/startup/GenerateInstrumentationServerClassesTest.java
+++ b/src/test/java/com/android/tools/r8/startup/GenerateInstrumentationServerClassesTest.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.cfmethodgeneration.CfClassGenerator;
 import com.android.tools.r8.graph.DexType;
-import com.android.tools.r8.utils.FileUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.nio.charset.StandardCharsets;
diff --git a/src/test/java/com/android/tools/r8/startup/diagnostic/MissingStartupProfileItemsDiagnosticTest.java b/src/test/java/com/android/tools/r8/startup/diagnostic/MissingStartupProfileItemsDiagnosticTest.java
index 5cf70dd..1be93c6 100644
--- a/src/test/java/com/android/tools/r8/startup/diagnostic/MissingStartupProfileItemsDiagnosticTest.java
+++ b/src/test/java/com/android/tools/r8/startup/diagnostic/MissingStartupProfileItemsDiagnosticTest.java
@@ -21,7 +21,7 @@
 import com.android.tools.r8.startup.StartupProfileProvider;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.MethodReferenceUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Collection;
 import java.util.Collections;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/startup/dump/DumpStartupProfileProvidersTest.java b/src/test/java/com/android/tools/r8/startup/dump/DumpStartupProfileProvidersTest.java
index 4726e0b..f4789f1 100644
--- a/src/test/java/com/android/tools/r8/startup/dump/DumpStartupProfileProvidersTest.java
+++ b/src/test/java/com/android/tools/r8/startup/dump/DumpStartupProfileProvidersTest.java
@@ -20,9 +20,9 @@
 import com.android.tools.r8.startup.StartupProfileProvider;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.DumpInputFlags;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.MethodReferenceUtils;
 import com.android.tools.r8.utils.ZipUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Lists;
 import java.io.IOException;
diff --git a/src/test/java/com/android/tools/r8/startup/utils/StartupTestingMatchers.java b/src/test/java/com/android/tools/r8/startup/utils/StartupTestingMatchers.java
index 618e644..6f768780 100644
--- a/src/test/java/com/android/tools/r8/startup/utils/StartupTestingMatchers.java
+++ b/src/test/java/com/android/tools/r8/startup/utils/StartupTestingMatchers.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.graph.DexProgramClass;
 import com.android.tools.r8.references.ClassReference;
 import com.android.tools.r8.references.TypeReference;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Collection;
 import java.util.Iterator;
 import org.hamcrest.Description;
diff --git a/src/test/java/com/android/tools/r8/startup/utils/StartupTestingUtils.java b/src/test/java/com/android/tools/r8/startup/utils/StartupTestingUtils.java
index 9504d4b..0e9e126 100644
--- a/src/test/java/com/android/tools/r8/startup/utils/StartupTestingUtils.java
+++ b/src/test/java/com/android/tools/r8/startup/utils/StartupTestingUtils.java
@@ -32,9 +32,9 @@
 import com.android.tools.r8.startup.profile.ExternalStartupMethod;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.Reporter;
-import com.android.tools.r8.utils.StringUtils;
-import com.android.tools.r8.utils.internal.ThrowingConsumer;
 import com.android.tools.r8.utils.UTF8TextInputStream;
+import com.android.tools.r8.utils.internal.StringUtils;
+import com.android.tools.r8.utils.internal.ThrowingConsumer;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import java.io.IOException;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/synthesis/RepeatedCompilationSyntheticsTest.java b/src/test/java/com/android/tools/r8/synthesis/RepeatedCompilationSyntheticsTest.java
index cd76ece..42ce335 100644
--- a/src/test/java/com/android/tools/r8/synthesis/RepeatedCompilationSyntheticsTest.java
+++ b/src/test/java/com/android/tools/r8/synthesis/RepeatedCompilationSyntheticsTest.java
@@ -15,7 +15,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.ListUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 import java.util.ArrayList;
diff --git a/src/test/java/com/android/tools/r8/synthesis/SyntheticMarkerCfTest.java b/src/test/java/com/android/tools/r8/synthesis/SyntheticMarkerCfTest.java
index f872bba..fd08e8f 100644
--- a/src/test/java/com/android/tools/r8/synthesis/SyntheticMarkerCfTest.java
+++ b/src/test/java/com/android/tools/r8/synthesis/SyntheticMarkerCfTest.java
@@ -16,9 +16,9 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.transformers.ClassTransformer;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.internal.Box;
 import com.android.tools.r8.utils.InternalOptions;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.Box;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.List;
diff --git a/src/test/java/com/android/tools/r8/synthesis/SyntheticMarkerDexTest.java b/src/test/java/com/android/tools/r8/synthesis/SyntheticMarkerDexTest.java
index 2420976..694ba0e 100644
--- a/src/test/java/com/android/tools/r8/synthesis/SyntheticMarkerDexTest.java
+++ b/src/test/java/com/android/tools/r8/synthesis/SyntheticMarkerDexTest.java
@@ -12,8 +12,8 @@
 import com.android.tools.r8.graph.DexEncodedAnnotation;
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/synthesis/globals/GlobalSyntheticOutputCliTest.java b/src/test/java/com/android/tools/r8/synthesis/globals/GlobalSyntheticOutputCliTest.java
index ba5d568..b888ca2 100644
--- a/src/test/java/com/android/tools/r8/synthesis/globals/GlobalSyntheticOutputCliTest.java
+++ b/src/test/java/com/android/tools/r8/synthesis/globals/GlobalSyntheticOutputCliTest.java
@@ -17,7 +17,7 @@
 import com.android.tools.r8.transformers.ClassFileTransformer.MethodPredicate;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.ListUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.nio.file.Files;
diff --git a/src/test/java/com/android/tools/r8/synthesis/globals/GlobalSyntheticStubContextRegressionTest.java b/src/test/java/com/android/tools/r8/synthesis/globals/GlobalSyntheticStubContextRegressionTest.java
index a269bf5..6db9919 100644
--- a/src/test/java/com/android/tools/r8/synthesis/globals/GlobalSyntheticStubContextRegressionTest.java
+++ b/src/test/java/com/android/tools/r8/synthesis/globals/GlobalSyntheticStubContextRegressionTest.java
@@ -15,7 +15,7 @@
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.transformers.ClassFileTransformer.MethodPredicate;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.nio.file.Path;
 import org.junit.Test;
diff --git a/src/test/java/com/android/tools/r8/testing/StackTraceTest.java b/src/test/java/com/android/tools/r8/testing/StackTraceTest.java
index 1cb04b5..9d11466 100644
--- a/src/test/java/com/android/tools/r8/testing/StackTraceTest.java
+++ b/src/test/java/com/android/tools/r8/testing/StackTraceTest.java
@@ -15,7 +15,7 @@
 import com.android.tools.r8.ToolHelper.DexVm;
 import com.android.tools.r8.naming.retrace.StackTrace;
 import com.android.tools.r8.naming.retrace.StackTrace.StackTraceLine;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/tracereferences/TraceReferenceNonReboundConstructorCallTest.java b/src/test/java/com/android/tools/r8/tracereferences/TraceReferenceNonReboundConstructorCallTest.java
index 358d6c9..ed942bc 100644
--- a/src/test/java/com/android/tools/r8/tracereferences/TraceReferenceNonReboundConstructorCallTest.java
+++ b/src/test/java/com/android/tools/r8/tracereferences/TraceReferenceNonReboundConstructorCallTest.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.tracereferences;
 
-import static com.android.tools.r8.utils.FileUtils.CLASS_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.CLASS_EXTENSION;
 import static org.junit.Assert.assertEquals;
 
 import com.android.tools.r8.DiagnosticsChecker;
diff --git a/src/test/java/com/android/tools/r8/tracereferences/TraceReferencesAnnotationClassConstantValuesReferencesInDexTest.java b/src/test/java/com/android/tools/r8/tracereferences/TraceReferencesAnnotationClassConstantValuesReferencesInDexTest.java
index 3abb1f6..0b4134e 100644
--- a/src/test/java/com/android/tools/r8/tracereferences/TraceReferencesAnnotationClassConstantValuesReferencesInDexTest.java
+++ b/src/test/java/com/android/tools/r8/tracereferences/TraceReferencesAnnotationClassConstantValuesReferencesInDexTest.java
@@ -16,7 +16,7 @@
 import com.android.tools.r8.references.MethodReference;
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
diff --git a/src/test/java/com/android/tools/r8/tracereferences/TraceReferencesAnnotationReferencesInDexTest.java b/src/test/java/com/android/tools/r8/tracereferences/TraceReferencesAnnotationReferencesInDexTest.java
index 48c90b8..6de3ef1 100644
--- a/src/test/java/com/android/tools/r8/tracereferences/TraceReferencesAnnotationReferencesInDexTest.java
+++ b/src/test/java/com/android/tools/r8/tracereferences/TraceReferencesAnnotationReferencesInDexTest.java
@@ -17,7 +17,7 @@
 import com.android.tools.r8.references.ClassReference;
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableSet;
 import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
diff --git a/src/test/java/com/android/tools/r8/tracereferences/TraceReferencesCommandTest.java b/src/test/java/com/android/tools/r8/tracereferences/TraceReferencesCommandTest.java
index 43f7a6b..5501710 100644
--- a/src/test/java/com/android/tools/r8/tracereferences/TraceReferencesCommandTest.java
+++ b/src/test/java/com/android/tools/r8/tracereferences/TraceReferencesCommandTest.java
@@ -31,10 +31,10 @@
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.DescriptorUtils;
 import com.android.tools.r8.utils.FieldReferenceUtils;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.MethodReferenceUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.ZipUtils.ZipBuilder;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
diff --git a/src/test/java/com/android/tools/r8/tracereferences/TraceReferencesDefaultMethodInSubInterfaceTest.java b/src/test/java/com/android/tools/r8/tracereferences/TraceReferencesDefaultMethodInSubInterfaceTest.java
index b32531c..08eb3bf 100644
--- a/src/test/java/com/android/tools/r8/tracereferences/TraceReferencesDefaultMethodInSubInterfaceTest.java
+++ b/src/test/java/com/android/tools/r8/tracereferences/TraceReferencesDefaultMethodInSubInterfaceTest.java
@@ -13,8 +13,8 @@
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.references.MethodReference;
 import com.android.tools.r8.references.Reference;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.ZipUtils.ZipBuilder;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableSet;
 import java.nio.file.Path;
 import java.util.Collections;
diff --git a/src/test/java/com/android/tools/r8/tracereferences/TraceReferencesDiagnosticTest.java b/src/test/java/com/android/tools/r8/tracereferences/TraceReferencesDiagnosticTest.java
index 11b792d..2acc397 100644
--- a/src/test/java/com/android/tools/r8/tracereferences/TraceReferencesDiagnosticTest.java
+++ b/src/test/java/com/android/tools/r8/tracereferences/TraceReferencesDiagnosticTest.java
@@ -21,8 +21,8 @@
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.DescriptorUtils;
 import com.android.tools.r8.utils.StringDiagnostic;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.ZipUtils.ZipBuilder;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java/com/android/tools/r8/tracereferences/TraceReferencesThrowsInDexTest.java b/src/test/java/com/android/tools/r8/tracereferences/TraceReferencesThrowsInDexTest.java
index 64f2428..79f344c 100644
--- a/src/test/java/com/android/tools/r8/tracereferences/TraceReferencesThrowsInDexTest.java
+++ b/src/test/java/com/android/tools/r8/tracereferences/TraceReferencesThrowsInDexTest.java
@@ -16,7 +16,7 @@
 import com.android.tools.r8.references.MethodReference;
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/utils/DaggerUtils.java b/src/test/java/com/android/tools/r8/utils/DaggerUtils.java
index e10cd49..071ed93 100644
--- a/src/test/java/com/android/tools/r8/utils/DaggerUtils.java
+++ b/src/test/java/com/android/tools/r8/utils/DaggerUtils.java
@@ -10,6 +10,7 @@
 import com.android.tools.r8.TestRuntime;
 import com.android.tools.r8.TestRuntime.CfRuntime;
 import com.android.tools.r8.ToolHelper;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.io.ByteStreams;
 import java.nio.file.Path;
diff --git a/src/test/java/com/android/tools/r8/utils/DataResourceConsumerForTesting.java b/src/test/java/com/android/tools/r8/utils/DataResourceConsumerForTesting.java
index c1b3522..af4aceb 100644
--- a/src/test/java/com/android/tools/r8/utils/DataResourceConsumerForTesting.java
+++ b/src/test/java/com/android/tools/r8/utils/DataResourceConsumerForTesting.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.utils;
 
-import static com.android.tools.r8.utils.StringUtils.UNIX_LINE_SEPARATOR;
+import static com.android.tools.r8.utils.internal.StringUtils.UNIX_LINE_SEPARATOR;
 import static org.junit.Assert.assertFalse;
 
 import com.android.tools.r8.DataDirectoryResource;
diff --git a/src/test/java/com/android/tools/r8/utils/GenerateMainDexListCommandTest.java b/src/test/java/com/android/tools/r8/utils/GenerateMainDexListCommandTest.java
index becf21f..ad62106 100644
--- a/src/test/java/com/android/tools/r8/utils/GenerateMainDexListCommandTest.java
+++ b/src/test/java/com/android/tools/r8/utils/GenerateMainDexListCommandTest.java
@@ -4,7 +4,7 @@
 package com.android.tools.r8.utils;
 
 import static com.android.tools.r8.ToolHelper.EXAMPLES_BUILD_DIR;
-import static com.android.tools.r8.utils.FileUtils.JAR_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.JAR_EXTENSION;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertTrue;
diff --git a/src/test/java/com/android/tools/r8/utils/StringUtilsTest.java b/src/test/java/com/android/tools/r8/utils/StringUtilsTest.java
index 2237b07..139ab2b 100644
--- a/src/test/java/com/android/tools/r8/utils/StringUtilsTest.java
+++ b/src/test/java/com/android/tools/r8/utils/StringUtilsTest.java
@@ -11,7 +11,8 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils.BraceType;
+import com.android.tools.r8.utils.internal.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils.BraceType;
 import com.google.common.base.Strings;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
diff --git a/src/test/java11/com/android/tools/r8/jdk10/desugaredlibrary/NewCollectorsTest.java b/src/test/java11/com/android/tools/r8/jdk10/desugaredlibrary/NewCollectorsTest.java
index 91b7b13..4423ce7 100644
--- a/src/test/java11/com/android/tools/r8/jdk10/desugaredlibrary/NewCollectorsTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk10/desugaredlibrary/NewCollectorsTest.java
@@ -17,9 +17,9 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.Collection;
 import java.util.List;
diff --git a/src/test/java11/com/android/tools/r8/jdk11/buffercovariantreturntype/BufferCovariantReturnTypeTest.java b/src/test/java11/com/android/tools/r8/jdk11/buffercovariantreturntype/BufferCovariantReturnTypeTest.java
index f812991..e3cc8ec 100644
--- a/src/test/java11/com/android/tools/r8/jdk11/buffercovariantreturntype/BufferCovariantReturnTypeTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk11/buffercovariantreturntype/BufferCovariantReturnTypeTest.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.Buffer;
 import java.nio.ByteBuffer;
 import java.nio.CharBuffer;
diff --git a/src/test/java11/com/android/tools/r8/jdk11/desugaredlibrary/CollectionToArrayTest.java b/src/test/java11/com/android/tools/r8/jdk11/desugaredlibrary/CollectionToArrayTest.java
index 3c4ed9e..f8e4c71 100644
--- a/src/test/java11/com/android/tools/r8/jdk11/desugaredlibrary/CollectionToArrayTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk11/desugaredlibrary/CollectionToArrayTest.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.DesugaredLibraryTestBase;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.ArrayList;
 import java.util.Arrays;
diff --git a/src/test/java11/com/android/tools/r8/jdk11/desugaredlibrary/FilesJava11Test.java b/src/test/java11/com/android/tools/r8/jdk11/desugaredlibrary/FilesJava11Test.java
index edc3d4b..e512955 100644
--- a/src/test/java11/com/android/tools/r8/jdk11/desugaredlibrary/FilesJava11Test.java
+++ b/src/test/java11/com/android/tools/r8/jdk11/desugaredlibrary/FilesJava11Test.java
@@ -14,9 +14,9 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.nio.charset.StandardCharsets;
diff --git a/src/test/java11/com/android/tools/r8/jdk11/desugaredlibrary/PathOfTest.java b/src/test/java11/com/android/tools/r8/jdk11/desugaredlibrary/PathOfTest.java
index e4c635b..6ae469f 100644
--- a/src/test/java11/com/android/tools/r8/jdk11/desugaredlibrary/PathOfTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk11/desugaredlibrary/PathOfTest.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.DesugaredLibraryTestBase;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Path;
 import java.util.List;
diff --git a/src/test/java11/com/android/tools/r8/jdk11/desugaredlibrary/StackWalkerTest.java b/src/test/java11/com/android/tools/r8/jdk11/desugaredlibrary/StackWalkerTest.java
index 280ceb5..399546f 100644
--- a/src/test/java11/com/android/tools/r8/jdk11/desugaredlibrary/StackWalkerTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk11/desugaredlibrary/StackWalkerTest.java
@@ -16,7 +16,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.lang.StackWalker.StackFrame;
 import java.util.List;
diff --git a/src/test/java11/com/android/tools/r8/jdk11/desugaredlibrary/TimeUnitTest.java b/src/test/java11/com/android/tools/r8/jdk11/desugaredlibrary/TimeUnitTest.java
index fa0413d..73200ef 100644
--- a/src/test/java11/com/android/tools/r8/jdk11/desugaredlibrary/TimeUnitTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk11/desugaredlibrary/TimeUnitTest.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.time.Duration;
 import java.time.temporal.ChronoUnit;
diff --git a/src/test/java11/com/android/tools/r8/jdk11/nest/FullNestOnProgramPathTest.java b/src/test/java11/com/android/tools/r8/jdk11/nest/FullNestOnProgramPathTest.java
index 81a70c6..573c5051 100644
--- a/src/test/java11/com/android/tools/r8/jdk11/nest/FullNestOnProgramPathTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk11/nest/FullNestOnProgramPathTest.java
@@ -24,10 +24,10 @@
 import com.android.tools.r8.ir.desugar.nest.NestBasedAccessDesugaring;
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FoundMethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import java.io.IOException;
diff --git a/src/test/java11/com/android/tools/r8/jdk11/nest/NestAttributesUpdateTest.java b/src/test/java11/com/android/tools/r8/jdk11/nest/NestAttributesUpdateTest.java
index 4f8e85a..a9cf7fb 100644
--- a/src/test/java11/com/android/tools/r8/jdk11/nest/NestAttributesUpdateTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk11/nest/NestAttributesUpdateTest.java
@@ -19,10 +19,10 @@
 import com.android.tools.r8.ThrowableConsumer;
 import com.android.tools.r8.graph.DexClass;
 import com.android.tools.r8.graph.NestMemberClassAttribute;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FoundClassSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java11/com/android/tools/r8/jdk11/nest/NestClassMergingTest.java b/src/test/java11/com/android/tools/r8/jdk11/nest/NestClassMergingTest.java
index b76ca35..e46be0c 100644
--- a/src/test/java11/com/android/tools/r8/jdk11/nest/NestClassMergingTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk11/nest/NestClassMergingTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java11/com/android/tools/r8/jdk11/nest/NestMethodInlinedTest.java b/src/test/java11/com/android/tools/r8/jdk11/nest/NestMethodInlinedTest.java
index 7f13a19..2dcfe5d 100644
--- a/src/test/java11/com/android/tools/r8/jdk11/nest/NestMethodInlinedTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk11/nest/NestMethodInlinedTest.java
@@ -11,11 +11,11 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FoundClassSubject;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java11/com/android/tools/r8/jdk11/nest/dex/NestAttributesInDexRewriteInvokeSpecialTest.java b/src/test/java11/com/android/tools/r8/jdk11/nest/dex/NestAttributesInDexRewriteInvokeSpecialTest.java
index 83f2676..d98df86 100644
--- a/src/test/java11/com/android/tools/r8/jdk11/nest/dex/NestAttributesInDexRewriteInvokeSpecialTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk11/nest/dex/NestAttributesInDexRewriteInvokeSpecialTest.java
@@ -13,10 +13,10 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.function.Predicate;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java11/com/android/tools/r8/jdk11/nest/dex/NestAttributesInDexShrinkingFieldsTest.java b/src/test/java11/com/android/tools/r8/jdk11/nest/dex/NestAttributesInDexShrinkingFieldsTest.java
index 2742121..d5ac057 100644
--- a/src/test/java11/com/android/tools/r8/jdk11/nest/dex/NestAttributesInDexShrinkingFieldsTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk11/nest/dex/NestAttributesInDexShrinkingFieldsTest.java
@@ -12,10 +12,10 @@
 
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.TypeSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java11/com/android/tools/r8/jdk11/nest/dex/NestAttributesInDexShrinkingMethodsTest.java b/src/test/java11/com/android/tools/r8/jdk11/nest/dex/NestAttributesInDexShrinkingMethodsTest.java
index 7e0d654..888d53d 100644
--- a/src/test/java11/com/android/tools/r8/jdk11/nest/dex/NestAttributesInDexShrinkingMethodsTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk11/nest/dex/NestAttributesInDexShrinkingMethodsTest.java
@@ -12,10 +12,10 @@
 
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.TypeSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java11/com/android/tools/r8/jdk11/nest/dex/NestAttributesInDexTest.java b/src/test/java11/com/android/tools/r8/jdk11/nest/dex/NestAttributesInDexTest.java
index 4122b8f..07cb645 100644
--- a/src/test/java11/com/android/tools/r8/jdk11/nest/dex/NestAttributesInDexTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk11/nest/dex/NestAttributesInDexTest.java
@@ -18,10 +18,10 @@
 import com.android.tools.r8.transformers.ClassFileTransformer;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.TypeSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.Arrays;
 import java.util.Collection;
diff --git a/src/test/java11/com/android/tools/r8/jdk11/string/StringConcatTest.java b/src/test/java11/com/android/tools/r8/jdk11/string/StringConcatTest.java
index 3d3dba5..84a8fa5 100644
--- a/src/test/java11/com/android/tools/r8/jdk11/string/StringConcatTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk11/string/StringConcatTest.java
@@ -15,11 +15,11 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.CodeMatchers;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java11/com/android/tools/r8/jdk9/desugaredlib/CollectionOfTest.java b/src/test/java11/com/android/tools/r8/jdk9/desugaredlib/CollectionOfTest.java
index 53e24de..bb4d0ac 100644
--- a/src/test/java11/com/android/tools/r8/jdk9/desugaredlib/CollectionOfTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk9/desugaredlib/CollectionOfTest.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import java.util.Set;
 import org.junit.Assume;
diff --git a/src/test/java11/com/android/tools/r8/jdk9/desugaredlib/InputStreamTransferToTest.java b/src/test/java11/com/android/tools/r8/jdk9/desugaredlib/InputStreamTransferToTest.java
index d686b0d..ccefdad 100644
--- a/src/test/java11/com/android/tools/r8/jdk9/desugaredlib/InputStreamTransferToTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk9/desugaredlib/InputStreamTransferToTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.DesugaredLibraryTestBase;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.ByteArrayInputStream;
 import java.io.ByteArrayOutputStream;
diff --git a/src/test/java11/com/android/tools/r8/jdk9/desugaredlib/JavaUtilOptionalTest.java b/src/test/java11/com/android/tools/r8/jdk9/desugaredlib/JavaUtilOptionalTest.java
index 9abddad..ece04c7 100644
--- a/src/test/java11/com/android/tools/r8/jdk9/desugaredlib/JavaUtilOptionalTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk9/desugaredlib/JavaUtilOptionalTest.java
@@ -16,11 +16,11 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.DesugaredLibraryTestCompileResult;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.jdk9.backport.OptionalBackportJava9Test;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.InvokeInstructionSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.Iterator;
 import java.util.List;
diff --git a/src/test/java11/com/android/tools/r8/jdk9/desugaredlib/NewLocalDateTest.java b/src/test/java11/com/android/tools/r8/jdk9/desugaredlib/NewLocalDateTest.java
index bd74f8d..cae87ee 100644
--- a/src/test/java11/com/android/tools/r8/jdk9/desugaredlib/NewLocalDateTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk9/desugaredlib/NewLocalDateTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.DesugaredLibraryTestBase;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.time.Instant;
 import java.time.LocalDate;
diff --git a/src/test/java11/com/android/tools/r8/jdk9/desugaredlib/NewTimeTest.java b/src/test/java11/com/android/tools/r8/jdk9/desugaredlib/NewTimeTest.java
index 9c9f550..1eb8325 100644
--- a/src/test/java11/com/android/tools/r8/jdk9/desugaredlib/NewTimeTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk9/desugaredlib/NewTimeTest.java
@@ -14,9 +14,9 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.time.Clock;
 import java.time.LocalDate;
diff --git a/src/test/java11/com/android/tools/r8/jdk9/desugaredlib/ProgramRewritingTest.java b/src/test/java11/com/android/tools/r8/jdk9/desugaredlib/ProgramRewritingTest.java
index 78ba2af..4691e1e 100644
--- a/src/test/java11/com/android/tools/r8/jdk9/desugaredlib/ProgramRewritingTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk9/desugaredlib/ProgramRewritingTest.java
@@ -24,11 +24,11 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.internal.Box;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
+import com.android.tools.r8.utils.internal.Box;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 import java.util.ArrayList;
diff --git a/src/test/java11/com/android/tools/r8/jdk9/desugaredlib/SynchronizedCollectionTest.java b/src/test/java11/com/android/tools/r8/jdk9/desugaredlib/SynchronizedCollectionTest.java
index 1320196..c4438e4 100644
--- a/src/test/java11/com/android/tools/r8/jdk9/desugaredlib/SynchronizedCollectionTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk9/desugaredlib/SynchronizedCollectionTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.DesugaredLibraryTestBase;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
diff --git a/src/test/java11/com/android/tools/r8/jdk9/desugaredlib/TimeZoneTest.java b/src/test/java11/com/android/tools/r8/jdk9/desugaredlib/TimeZoneTest.java
index 0e5e6d1..9a22246 100644
--- a/src/test/java11/com/android/tools/r8/jdk9/desugaredlib/TimeZoneTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk9/desugaredlib/TimeZoneTest.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.DesugaredLibraryTestBase;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.text.ParseException;
 import java.text.SimpleDateFormat;
diff --git a/src/test/java11/com/android/tools/r8/jdk9/desugaredlib/flow/Flow2Test.java b/src/test/java11/com/android/tools/r8/jdk9/desugaredlib/flow/Flow2Test.java
index 96643cd..5061797 100644
--- a/src/test/java11/com/android/tools/r8/jdk9/desugaredlib/flow/Flow2Test.java
+++ b/src/test/java11/com/android/tools/r8/jdk9/desugaredlib/flow/Flow2Test.java
@@ -17,9 +17,9 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CustomLibrarySpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FoundMethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import java.util.concurrent.Flow.Publisher;
diff --git a/src/test/java11/com/android/tools/r8/jdk9/desugaredlib/flow/FlowTest.java b/src/test/java11/com/android/tools/r8/jdk9/desugaredlib/flow/FlowTest.java
index 145cfd6..96f436e 100644
--- a/src/test/java11/com/android/tools/r8/jdk9/desugaredlib/flow/FlowTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk9/desugaredlib/flow/FlowTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.DesugaredLibraryTestBase;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java11/com/android/tools/r8/jdk9/stringconcatfactory/StringConcatFactoryTest.java b/src/test/java11/com/android/tools/r8/jdk9/stringconcatfactory/StringConcatFactoryTest.java
index 9fb074a..b0a1285 100644
--- a/src/test/java11/com/android/tools/r8/jdk9/stringconcatfactory/StringConcatFactoryTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk9/stringconcatfactory/StringConcatFactoryTest.java
@@ -21,9 +21,9 @@
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.diagnostic.MissingDefinitionsDiagnostic;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java11/com/android/tools/r8/jdk9/twr/twraddsuppressed/TwrSuppressedExceptionsTest.java b/src/test/java11/com/android/tools/r8/jdk9/twr/twraddsuppressed/TwrSuppressedExceptionsTest.java
index c4b9f19..edb9b5b 100644
--- a/src/test/java11/com/android/tools/r8/jdk9/twr/twraddsuppressed/TwrSuppressedExceptionsTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk9/twr/twraddsuppressed/TwrSuppressedExceptionsTest.java
@@ -14,11 +14,11 @@
 import com.android.tools.r8.jdk9.twr.twraddsuppressed.asm.TestClass$MyClosableDump;
 import com.android.tools.r8.jdk9.twr.twraddsuppressed.asm.TestClassDump;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.internal.IntBox;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.IntBox;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import java.util.concurrent.ForkJoinPool;
diff --git a/src/test/java11/com/android/tools/r8/jdk9/twr/twrcloseresource/TwrCloseResourceRunnerTest.java b/src/test/java11/com/android/tools/r8/jdk9/twr/twrcloseresource/TwrCloseResourceRunnerTest.java
index 1d600c3..0390010 100644
--- a/src/test/java11/com/android/tools/r8/jdk9/twr/twrcloseresource/TwrCloseResourceRunnerTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk9/twr/twrcloseresource/TwrCloseResourceRunnerTest.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.jdk9.twr.twrcloseresource.asm.TwrCloseResourceTestDump;
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Path;
 import java.nio.file.Paths;
diff --git a/src/test/java11/com/android/tools/r8/jdk9/twr/twrcloseresourceduplication/TwrCloseResourceDuplicationTest.java b/src/test/java11/com/android/tools/r8/jdk9/twr/twrcloseresourceduplication/TwrCloseResourceDuplicationTest.java
index ab2fc7d..c1458a8 100644
--- a/src/test/java11/com/android/tools/r8/jdk9/twr/twrcloseresourceduplication/TwrCloseResourceDuplicationTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk9/twr/twrcloseresourceduplication/TwrCloseResourceDuplicationTest.java
@@ -16,9 +16,9 @@
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.InternalOptions;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.ZipUtils;
 import com.android.tools.r8.utils.codeinspector.FoundClassSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 import java.io.IOException;
diff --git a/src/test/java11/com/android/tools/r8/jdk9/varhandle/MethodHandlesPrivateLookupInTest.java b/src/test/java11/com/android/tools/r8/jdk9/varhandle/MethodHandlesPrivateLookupInTest.java
index ffbb062..fa906db 100644
--- a/src/test/java11/com/android/tools/r8/jdk9/varhandle/MethodHandlesPrivateLookupInTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk9/varhandle/MethodHandlesPrivateLookupInTest.java
@@ -5,7 +5,7 @@
 package com.android.tools.r8.jdk9.varhandle;
 
 import com.android.tools.r8.jdk9.varhandle.util.WithPrivateFields;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.runner.RunWith;
diff --git a/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringArrayOfIntTest.java b/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringArrayOfIntTest.java
index 4316a8b..1fdfbaa 100644
--- a/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringArrayOfIntTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringArrayOfIntTest.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.jdk9.varhandle;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.runner.RunWith;
diff --git a/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringArrayOfLongTest.java b/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringArrayOfLongTest.java
index 9b1fe08..c7012cd 100644
--- a/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringArrayOfLongTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringArrayOfLongTest.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.jdk9.varhandle;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.runner.RunWith;
diff --git a/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringArrayOfObjectTest.java b/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringArrayOfObjectTest.java
index 6a065d1..24bcb0d 100644
--- a/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringArrayOfObjectTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringArrayOfObjectTest.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.jdk9.varhandle;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.runner.RunWith;
diff --git a/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringInstanceBooleanFieldTest.java b/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringInstanceBooleanFieldTest.java
index 9defea0..45d6c26 100644
--- a/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringInstanceBooleanFieldTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringInstanceBooleanFieldTest.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.jdk9.varhandle;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.runner.RunWith;
diff --git a/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringInstanceByteFieldTest.java b/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringInstanceByteFieldTest.java
index cf60dad..6ebc8b5 100644
--- a/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringInstanceByteFieldTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringInstanceByteFieldTest.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.jdk9.varhandle;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.runner.RunWith;
diff --git a/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringInstanceDoubleFieldTest.java b/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringInstanceDoubleFieldTest.java
index 0b05cf2..47d4a63 100644
--- a/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringInstanceDoubleFieldTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringInstanceDoubleFieldTest.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.jdk9.varhandle;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.runner.RunWith;
diff --git a/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringInstanceFloatFieldTest.java b/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringInstanceFloatFieldTest.java
index 80c978c..5d688ad 100644
--- a/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringInstanceFloatFieldTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringInstanceFloatFieldTest.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.jdk9.varhandle;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.runner.RunWith;
diff --git a/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringInstanceIntFieldTest.java b/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringInstanceIntFieldTest.java
index 86a94a7..26b26ed 100644
--- a/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringInstanceIntFieldTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringInstanceIntFieldTest.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.jdk9.varhandle;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.runner.RunWith;
diff --git a/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringInstanceLongFieldTest.java b/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringInstanceLongFieldTest.java
index dfa68c8..f0da544 100644
--- a/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringInstanceLongFieldTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringInstanceLongFieldTest.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.jdk9.varhandle;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.runner.RunWith;
diff --git a/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringInstanceObjectFieldTest.java b/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringInstanceObjectFieldTest.java
index af334ce..6670eba 100644
--- a/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringInstanceObjectFieldTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringInstanceObjectFieldTest.java
@@ -5,7 +5,7 @@
 package com.android.tools.r8.jdk9.varhandle;
 
 import com.android.tools.r8.ToolHelper.DexVm.Version;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.runner.RunWith;
diff --git a/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringInstanceShortFieldTest.java b/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringInstanceShortFieldTest.java
index 46bef10..7969844 100644
--- a/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringInstanceShortFieldTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringInstanceShortFieldTest.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.jdk9.varhandle;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.runner.RunWith;
diff --git a/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringInstanceStringFieldTest.java b/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringInstanceStringFieldTest.java
index 7706683..cf27b81 100644
--- a/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringInstanceStringFieldTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleDesugaringInstanceStringFieldTest.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.jdk9.varhandle;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.runner.RunWith;
diff --git a/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleNoDesugaredTypesInSignaturesNoAttributesTest.java b/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleNoDesugaredTypesInSignaturesNoAttributesTest.java
index d55c86d..11a5217 100644
--- a/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleNoDesugaredTypesInSignaturesNoAttributesTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleNoDesugaredTypesInSignaturesNoAttributesTest.java
@@ -14,8 +14,8 @@
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.ToolHelper.DexVm.Version;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleNoDesugaredTypesInSignaturesTest.java b/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleNoDesugaredTypesInSignaturesTest.java
index 5663314..ccc4091 100644
--- a/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleNoDesugaredTypesInSignaturesTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleNoDesugaredTypesInSignaturesTest.java
@@ -4,7 +4,7 @@
 
 package com.android.tools.r8.jdk9.varhandle;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.runner.RunWith;
diff --git a/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleTest.java b/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleTest.java
index b4dcf0c..8bb7692 100644
--- a/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleTest.java
+++ b/src/test/java11/com/android/tools/r8/jdk9/varhandle/VarHandleTest.java
@@ -16,7 +16,7 @@
 import com.android.tools.r8.ToolHelper.DexVm.Version;
 import com.android.tools.r8.errors.UnsupportedInvokePolymorphicMethodHandleDiagnostic;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java17/com/android/tools/r8/jdk17/desugaredlibrary/desugaredlibrary/InstantSourceApiTest.java b/src/test/java17/com/android/tools/r8/jdk17/desugaredlibrary/desugaredlibrary/InstantSourceApiTest.java
index f79ad7a..2cb8a2b 100644
--- a/src/test/java17/com/android/tools/r8/jdk17/desugaredlibrary/desugaredlibrary/InstantSourceApiTest.java
+++ b/src/test/java17/com/android/tools/r8/jdk17/desugaredlibrary/desugaredlibrary/InstantSourceApiTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.time.Clock;
 import java.time.Instant;
diff --git a/src/test/java17/com/android/tools/r8/jdk17/desugaredlibrary/desugaredlibrary/InstantSourceArrayTest.java b/src/test/java17/com/android/tools/r8/jdk17/desugaredlibrary/desugaredlibrary/InstantSourceArrayTest.java
index f33b424..3e90ee9 100644
--- a/src/test/java17/com/android/tools/r8/jdk17/desugaredlibrary/desugaredlibrary/InstantSourceArrayTest.java
+++ b/src/test/java17/com/android/tools/r8/jdk17/desugaredlibrary/desugaredlibrary/InstantSourceArrayTest.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.time.Clock;
 import java.time.Duration;
diff --git a/src/test/java17/com/android/tools/r8/jdk17/desugaredlibrary/desugaredlibrary/InstantSourceTest.java b/src/test/java17/com/android/tools/r8/jdk17/desugaredlibrary/desugaredlibrary/InstantSourceTest.java
index 6c23a3a..c1301e3 100644
--- a/src/test/java17/com/android/tools/r8/jdk17/desugaredlibrary/desugaredlibrary/InstantSourceTest.java
+++ b/src/test/java17/com/android/tools/r8/jdk17/desugaredlibrary/desugaredlibrary/InstantSourceTest.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.time.Clock;
 import java.time.Duration;
diff --git a/src/test/java17/com/android/tools/r8/jdk17/desugaredlibrary/desugaredlibrary/StreamToListTest.java b/src/test/java17/com/android/tools/r8/jdk17/desugaredlibrary/desugaredlibrary/StreamToListTest.java
index 43502d8..7fda246 100644
--- a/src/test/java17/com/android/tools/r8/jdk17/desugaredlibrary/desugaredlibrary/StreamToListTest.java
+++ b/src/test/java17/com/android/tools/r8/jdk17/desugaredlibrary/desugaredlibrary/StreamToListTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.DesugaredLibraryTestBase;
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import java.util.stream.Stream;
diff --git a/src/test/java17/com/android/tools/r8/jdk17/enumStatic/StaticEnumMergingTest.java b/src/test/java17/com/android/tools/r8/jdk17/enumStatic/StaticEnumMergingTest.java
index 68ac889..5c58ed5 100644
--- a/src/test/java17/com/android/tools/r8/jdk17/enumStatic/StaticEnumMergingTest.java
+++ b/src/test/java17/com/android/tools/r8/jdk17/enumStatic/StaticEnumMergingTest.java
@@ -6,7 +6,7 @@
 
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.enumunboxing.EnumUnboxingTestBase;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java17/com/android/tools/r8/jdk17/enum_sealed/SealedClassesEnumJdk17CompiledTest.java b/src/test/java17/com/android/tools/r8/jdk17/enum_sealed/SealedClassesEnumJdk17CompiledTest.java
index e3654f9..721bfc8 100644
--- a/src/test/java17/com/android/tools/r8/jdk17/enum_sealed/SealedClassesEnumJdk17CompiledTest.java
+++ b/src/test/java17/com/android/tools/r8/jdk17/enum_sealed/SealedClassesEnumJdk17CompiledTest.java
@@ -14,10 +14,10 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.TestShrinkerBuilder;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java17/com/android/tools/r8/jdk17/nest/NestLambdaJava17Test.java b/src/test/java17/com/android/tools/r8/jdk17/nest/NestLambdaJava17Test.java
index 238cb21..824d1bb 100644
--- a/src/test/java17/com/android/tools/r8/jdk17/nest/NestLambdaJava17Test.java
+++ b/src/test/java17/com/android/tools/r8/jdk17/nest/NestLambdaJava17Test.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java17/com/android/tools/r8/jdk17/records/EmptyRecordAnnotationTest.java b/src/test/java17/com/android/tools/r8/jdk17/records/EmptyRecordAnnotationTest.java
index 19816a7..c9651b4 100644
--- a/src/test/java17/com/android/tools/r8/jdk17/records/EmptyRecordAnnotationTest.java
+++ b/src/test/java17/com/android/tools/r8/jdk17/records/EmptyRecordAnnotationTest.java
@@ -9,9 +9,9 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 import org.junit.Test;
diff --git a/src/test/java17/com/android/tools/r8/jdk17/records/EmptyRecordTest.java b/src/test/java17/com/android/tools/r8/jdk17/records/EmptyRecordTest.java
index 1b5b2ce..8703dc0 100644
--- a/src/test/java17/com/android/tools/r8/jdk17/records/EmptyRecordTest.java
+++ b/src/test/java17/com/android/tools/r8/jdk17/records/EmptyRecordTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.hamcrest.Matcher;
 import org.junit.Test;
diff --git a/src/test/java17/com/android/tools/r8/jdk17/records/RecordBlogTest.java b/src/test/java17/com/android/tools/r8/jdk17/records/RecordBlogTest.java
index a6b8a2f..c95f839 100644
--- a/src/test/java17/com/android/tools/r8/jdk17/records/RecordBlogTest.java
+++ b/src/test/java17/com/android/tools/r8/jdk17/records/RecordBlogTest.java
@@ -15,7 +15,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableMap;
 import java.util.HashMap;
 import java.util.Map;
diff --git a/src/test/java17/com/android/tools/r8/jdk17/records/RecordClasspathTest.java b/src/test/java17/com/android/tools/r8/jdk17/records/RecordClasspathTest.java
index 8b8cc73..1dfff27 100644
--- a/src/test/java17/com/android/tools/r8/jdk17/records/RecordClasspathTest.java
+++ b/src/test/java17/com/android/tools/r8/jdk17/records/RecordClasspathTest.java
@@ -18,9 +18,9 @@
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.transformers.ClassFileTransformer.FieldPredicate;
 import com.android.tools.r8.transformers.ClassFileTransformer.MethodPredicate;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.nio.file.Files;
 import java.util.List;
diff --git a/src/test/java17/com/android/tools/r8/jdk17/records/RecordComponentAnnotationsTest.java b/src/test/java17/com/android/tools/r8/jdk17/records/RecordComponentAnnotationsTest.java
index a4f145a..2b72fed 100644
--- a/src/test/java17/com/android/tools/r8/jdk17/records/RecordComponentAnnotationsTest.java
+++ b/src/test/java17/com/android/tools/r8/jdk17/records/RecordComponentAnnotationsTest.java
@@ -17,10 +17,10 @@
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.TestShrinkerBuilder;
 import com.android.tools.r8.ToolHelper;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.FieldSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.collections.Pair;
 import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
diff --git a/src/test/java17/com/android/tools/r8/jdk17/records/RecordComponentSignatureTest.java b/src/test/java17/com/android/tools/r8/jdk17/records/RecordComponentSignatureTest.java
index 24a83c7..fc3a59f 100644
--- a/src/test/java17/com/android/tools/r8/jdk17/records/RecordComponentSignatureTest.java
+++ b/src/test/java17/com/android/tools/r8/jdk17/records/RecordComponentSignatureTest.java
@@ -14,10 +14,10 @@
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.TestShrinkerBuilder;
 import com.android.tools.r8.ToolHelper;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.FieldSubject;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.lang.reflect.RecordComponent;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java17/com/android/tools/r8/jdk17/records/RecordHashCodeManyFieldsTest.java b/src/test/java17/com/android/tools/r8/jdk17/records/RecordHashCodeManyFieldsTest.java
index abf6961..b10ef03 100644
--- a/src/test/java17/com/android/tools/r8/jdk17/records/RecordHashCodeManyFieldsTest.java
+++ b/src/test/java17/com/android/tools/r8/jdk17/records/RecordHashCodeManyFieldsTest.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Objects;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java17/com/android/tools/r8/jdk17/records/RecordHashCodeTest.java b/src/test/java17/com/android/tools/r8/jdk17/records/RecordHashCodeTest.java
index 6c5bfe6..616633b 100644
--- a/src/test/java17/com/android/tools/r8/jdk17/records/RecordHashCodeTest.java
+++ b/src/test/java17/com/android/tools/r8/jdk17/records/RecordHashCodeTest.java
@@ -14,7 +14,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java17/com/android/tools/r8/jdk17/records/RecordInstanceOfTest.java b/src/test/java17/com/android/tools/r8/jdk17/records/RecordInstanceOfTest.java
index 10cf087..3a37e95 100644
--- a/src/test/java17/com/android/tools/r8/jdk17/records/RecordInstanceOfTest.java
+++ b/src/test/java17/com/android/tools/r8/jdk17/records/RecordInstanceOfTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java17/com/android/tools/r8/jdk17/records/RecordInterfaceTest.java b/src/test/java17/com/android/tools/r8/jdk17/records/RecordInterfaceTest.java
index f885bce..2e10a36 100644
--- a/src/test/java17/com/android/tools/r8/jdk17/records/RecordInterfaceTest.java
+++ b/src/test/java17/com/android/tools/r8/jdk17/records/RecordInterfaceTest.java
@@ -19,7 +19,7 @@
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.origin.PathOrigin;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.nio.file.Files;
diff --git a/src/test/java17/com/android/tools/r8/jdk17/records/RecordInvokeCustomSplitDesugaringTest.java b/src/test/java17/com/android/tools/r8/jdk17/records/RecordInvokeCustomSplitDesugaringTest.java
index 00ba364..e0734da 100644
--- a/src/test/java17/com/android/tools/r8/jdk17/records/RecordInvokeCustomSplitDesugaringTest.java
+++ b/src/test/java17/com/android/tools/r8/jdk17/records/RecordInvokeCustomSplitDesugaringTest.java
@@ -19,10 +19,10 @@
 import com.android.tools.r8.errors.UnusedProguardKeepRuleDiagnostic;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.StringDiagnostic;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.ZipUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.internal.ArrayUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java17/com/android/tools/r8/jdk17/records/RecordInvokeCustomTest.java b/src/test/java17/com/android/tools/r8/jdk17/records/RecordInvokeCustomTest.java
index f4e83ba..da30427 100644
--- a/src/test/java17/com/android/tools/r8/jdk17/records/RecordInvokeCustomTest.java
+++ b/src/test/java17/com/android/tools/r8/jdk17/records/RecordInvokeCustomTest.java
@@ -14,9 +14,9 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfRuntime;
 import com.android.tools.r8.TestRuntime.CfVm;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java17/com/android/tools/r8/jdk17/records/RecordKeepRulesTest.java b/src/test/java17/com/android/tools/r8/jdk17/records/RecordKeepRulesTest.java
index f888b3e..f6283d3 100644
--- a/src/test/java17/com/android/tools/r8/jdk17/records/RecordKeepRulesTest.java
+++ b/src/test/java17/com/android/tools/r8/jdk17/records/RecordKeepRulesTest.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java17/com/android/tools/r8/jdk17/records/RecordLibMergeTest.java b/src/test/java17/com/android/tools/r8/jdk17/records/RecordLibMergeTest.java
index 003f45a..c30662d 100644
--- a/src/test/java17/com/android/tools/r8/jdk17/records/RecordLibMergeTest.java
+++ b/src/test/java17/com/android/tools/r8/jdk17/records/RecordLibMergeTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java17/com/android/tools/r8/jdk17/records/RecordMergeTest.java b/src/test/java17/com/android/tools/r8/jdk17/records/RecordMergeTest.java
index 30f5bf3..0a1e1e0 100644
--- a/src/test/java17/com/android/tools/r8/jdk17/records/RecordMergeTest.java
+++ b/src/test/java17/com/android/tools/r8/jdk17/records/RecordMergeTest.java
@@ -23,8 +23,8 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.errors.DuplicateTypesDiagnostic;
 import com.android.tools.r8.errors.MissingGlobalSyntheticsConsumerDiagnostic;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java17/com/android/tools/r8/jdk17/records/RecordProfileRewritingTest.java b/src/test/java17/com/android/tools/r8/jdk17/records/RecordProfileRewritingTest.java
index 1261c2e..be8f5a0 100644
--- a/src/test/java17/com/android/tools/r8/jdk17/records/RecordProfileRewritingTest.java
+++ b/src/test/java17/com/android/tools/r8/jdk17/records/RecordProfileRewritingTest.java
@@ -28,10 +28,10 @@
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
 import com.android.tools.r8.utils.InternalOptions.InlinerOptions;
 import com.android.tools.r8.utils.MethodReferenceUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.Collections;
 import org.junit.Test;
diff --git a/src/test/java17/com/android/tools/r8/jdk17/records/RecordReflectionTest.java b/src/test/java17/com/android/tools/r8/jdk17/records/RecordReflectionTest.java
index 373789e..ebd2be2 100644
--- a/src/test/java17/com/android/tools/r8/jdk17/records/RecordReflectionTest.java
+++ b/src/test/java17/com/android/tools/r8/jdk17/records/RecordReflectionTest.java
@@ -9,7 +9,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java17/com/android/tools/r8/jdk17/records/RecordShrinkFieldTest.java b/src/test/java17/com/android/tools/r8/jdk17/records/RecordShrinkFieldTest.java
index 9610af7..816478d 100644
--- a/src/test/java17/com/android/tools/r8/jdk17/records/RecordShrinkFieldTest.java
+++ b/src/test/java17/com/android/tools/r8/jdk17/records/RecordShrinkFieldTest.java
@@ -13,10 +13,10 @@
 import com.android.tools.r8.JdkClassFileProvider;
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.List;
 import org.hamcrest.Matcher;
diff --git a/src/test/java17/com/android/tools/r8/jdk17/records/RecordWithMembersTest.java b/src/test/java17/com/android/tools/r8/jdk17/records/RecordWithMembersTest.java
index 3c8c193..8958dc4 100644
--- a/src/test/java17/com/android/tools/r8/jdk17/records/RecordWithMembersTest.java
+++ b/src/test/java17/com/android/tools/r8/jdk17/records/RecordWithMembersTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java17/com/android/tools/r8/jdk17/records/RecordWithNonMaterializableConstClassTest.java b/src/test/java17/com/android/tools/r8/jdk17/records/RecordWithNonMaterializableConstClassTest.java
index d4dd5d0..4fd554f 100644
--- a/src/test/java17/com/android/tools/r8/jdk17/records/RecordWithNonMaterializableConstClassTest.java
+++ b/src/test/java17/com/android/tools/r8/jdk17/records/RecordWithNonMaterializableConstClassTest.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.jdk17.records.differentpackage.PrivateConstClass;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java17/com/android/tools/r8/jdk17/records/SimpleRecordTest.java b/src/test/java17/com/android/tools/r8/jdk17/records/SimpleRecordTest.java
index ba60748..e7e1e6a 100644
--- a/src/test/java17/com/android/tools/r8/jdk17/records/SimpleRecordTest.java
+++ b/src/test/java17/com/android/tools/r8/jdk17/records/SimpleRecordTest.java
@@ -15,9 +15,9 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.internal.BooleanUtils;
 import com.android.tools.r8.utils.InternalOptions;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.nio.file.Path;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java17/com/android/tools/r8/jdk17/records/UnusedRecordFieldTest.java b/src/test/java17/com/android/tools/r8/jdk17/records/UnusedRecordFieldTest.java
index 213056d..8e7906b 100644
--- a/src/test/java17/com/android/tools/r8/jdk17/records/UnusedRecordFieldTest.java
+++ b/src/test/java17/com/android/tools/r8/jdk17/records/UnusedRecordFieldTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java17/com/android/tools/r8/jdk17/records/UnusedRecordMethodTest.java b/src/test/java17/com/android/tools/r8/jdk17/records/UnusedRecordMethodTest.java
index 7a8da22..d4b327d 100644
--- a/src/test/java17/com/android/tools/r8/jdk17/records/UnusedRecordMethodTest.java
+++ b/src/test/java17/com/android/tools/r8/jdk17/records/UnusedRecordMethodTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java17/com/android/tools/r8/jdk17/records/UnusedRecordReflectionTest.java b/src/test/java17/com/android/tools/r8/jdk17/records/UnusedRecordReflectionTest.java
index 3f11c14..3a32561 100644
--- a/src/test/java17/com/android/tools/r8/jdk17/records/UnusedRecordReflectionTest.java
+++ b/src/test/java17/com/android/tools/r8/jdk17/records/UnusedRecordReflectionTest.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.lang.reflect.Method;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java17/com/android/tools/r8/jdk17/sealed/SealedClassesJdk17CompiledTest.java b/src/test/java17/com/android/tools/r8/jdk17/sealed/SealedClassesJdk17CompiledTest.java
index fd0bacb..42949a9 100644
--- a/src/test/java17/com/android/tools/r8/jdk17/sealed/SealedClassesJdk17CompiledTest.java
+++ b/src/test/java17/com/android/tools/r8/jdk17/sealed/SealedClassesJdk17CompiledTest.java
@@ -14,10 +14,10 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.TestShrinkerBuilder;
-import com.android.tools.r8.utils.internal.BooleanUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import org.junit.Test;
diff --git a/src/test/java17/com/android/tools/r8/jdk17/string/StringBuilderWithAppendOutOfBoundsTest.java b/src/test/java17/com/android/tools/r8/jdk17/string/StringBuilderWithAppendOutOfBoundsTest.java
index 502d922..bfcf3e4 100644
--- a/src/test/java17/com/android/tools/r8/jdk17/string/StringBuilderWithAppendOutOfBoundsTest.java
+++ b/src/test/java17/com/android/tools/r8/jdk17/string/StringBuilderWithAppendOutOfBoundsTest.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ToolHelper;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java21/com/android/tools/r8/jdk21/assistant/JavaLangClass21Test.java b/src/test/java21/com/android/tools/r8/jdk21/assistant/JavaLangClass21Test.java
index 87749b0..9751458 100644
--- a/src/test/java21/com/android/tools/r8/jdk21/assistant/JavaLangClass21Test.java
+++ b/src/test/java21/com/android/tools/r8/jdk21/assistant/JavaLangClass21Test.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.assistant.runtime.ReflectiveOracle.Stack;
 import com.android.tools.r8.jdk21.assistant.JavaLangTestClass21.Foo;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java21/com/android/tools/r8/jdk21/autocloseable/AutoCloseableRetargeterExecutorServiceSubtypeTest.java b/src/test/java21/com/android/tools/r8/jdk21/autocloseable/AutoCloseableRetargeterExecutorServiceSubtypeTest.java
index 608686c..2335071 100644
--- a/src/test/java21/com/android/tools/r8/jdk21/autocloseable/AutoCloseableRetargeterExecutorServiceSubtypeTest.java
+++ b/src/test/java21/com/android/tools/r8/jdk21/autocloseable/AutoCloseableRetargeterExecutorServiceSubtypeTest.java
@@ -15,9 +15,9 @@
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.Collection;
 import java.util.List;
diff --git a/src/test/java21/com/android/tools/r8/jdk21/autocloseable/AutoCloseableRetargeterExecutorServiceSubtypeTwrTest.java b/src/test/java21/com/android/tools/r8/jdk21/autocloseable/AutoCloseableRetargeterExecutorServiceSubtypeTwrTest.java
index ef5b8e7..697f000 100644
--- a/src/test/java21/com/android/tools/r8/jdk21/autocloseable/AutoCloseableRetargeterExecutorServiceSubtypeTwrTest.java
+++ b/src/test/java21/com/android/tools/r8/jdk21/autocloseable/AutoCloseableRetargeterExecutorServiceSubtypeTwrTest.java
@@ -13,13 +13,11 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.ToolHelper;
-import com.android.tools.r8.jdk21.autocloseable.AutoCloseableRetargeterExecutorServiceSubtypeTest.Executor2;
-import com.android.tools.r8.jdk21.autocloseable.AutoCloseableRetargeterExecutorServiceSubtypeTest.PrintForkJoinPool;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.DeterminismChecker;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.nio.file.Files;
 import java.nio.file.Path;
diff --git a/src/test/java21/com/android/tools/r8/jdk21/autocloseable/AutoCloseableRetargeterExecutorServiceTest.java b/src/test/java21/com/android/tools/r8/jdk21/autocloseable/AutoCloseableRetargeterExecutorServiceTest.java
index b636b85..0cdf647 100644
--- a/src/test/java21/com/android/tools/r8/jdk21/autocloseable/AutoCloseableRetargeterExecutorServiceTest.java
+++ b/src/test/java21/com/android/tools/r8/jdk21/autocloseable/AutoCloseableRetargeterExecutorServiceTest.java
@@ -12,7 +12,7 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.ForkJoinPool;
 import java.util.concurrent.ScheduledThreadPoolExecutor;
diff --git a/src/test/java21/com/android/tools/r8/jdk21/backport/Jdk21Float16Test.java b/src/test/java21/com/android/tools/r8/jdk21/backport/Jdk21Float16Test.java
index 23b00dd..a562de1 100644
--- a/src/test/java21/com/android/tools/r8/jdk21/backport/Jdk21Float16Test.java
+++ b/src/test/java21/com/android/tools/r8/jdk21/backport/Jdk21Float16Test.java
@@ -4,8 +4,8 @@
 
 package com.android.tools.r8.jdk21.backport;
 
-import static com.android.tools.r8.utils.FileUtils.CLASS_EXTENSION;
-import static com.android.tools.r8.utils.FileUtils.JAVA_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.CLASS_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.JAVA_EXTENSION;
 
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParameters;
diff --git a/src/test/java21/com/android/tools/r8/jdk21/desugaredlibrary/DurationIsPositiveTest.java b/src/test/java21/com/android/tools/r8/jdk21/desugaredlibrary/DurationIsPositiveTest.java
index c91ec95..ccb8991 100644
--- a/src/test/java21/com/android/tools/r8/jdk21/desugaredlibrary/DurationIsPositiveTest.java
+++ b/src/test/java21/com/android/tools/r8/jdk21/desugaredlibrary/DurationIsPositiveTest.java
@@ -16,7 +16,7 @@
 import com.android.tools.r8.desugar.desugaredlibrary.test.CompilationSpecification;
 import com.android.tools.r8.desugar.desugaredlibrary.test.LibraryDesugaringSpecification;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.time.Duration;
 import java.util.List;
diff --git a/src/test/java21/com/android/tools/r8/jdk21/switchpatternmatching/EnumLessCasesAtRuntimeSwitchTest.java b/src/test/java21/com/android/tools/r8/jdk21/switchpatternmatching/EnumLessCasesAtRuntimeSwitchTest.java
index 4b950eb..157c845 100644
--- a/src/test/java21/com/android/tools/r8/jdk21/switchpatternmatching/EnumLessCasesAtRuntimeSwitchTest.java
+++ b/src/test/java21/com/android/tools/r8/jdk21/switchpatternmatching/EnumLessCasesAtRuntimeSwitchTest.java
@@ -15,8 +15,8 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.ToolHelper;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java21/com/android/tools/r8/jdk21/switchpatternmatching/EnumMoreCasesAtRuntimeSwitchTest.java b/src/test/java21/com/android/tools/r8/jdk21/switchpatternmatching/EnumMoreCasesAtRuntimeSwitchTest.java
index 961d65d..886bb32 100644
--- a/src/test/java21/com/android/tools/r8/jdk21/switchpatternmatching/EnumMoreCasesAtRuntimeSwitchTest.java
+++ b/src/test/java21/com/android/tools/r8/jdk21/switchpatternmatching/EnumMoreCasesAtRuntimeSwitchTest.java
@@ -17,8 +17,8 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.ToolHelper;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java21/com/android/tools/r8/jdk21/switchpatternmatching/EnumSwitchTest.java b/src/test/java21/com/android/tools/r8/jdk21/switchpatternmatching/EnumSwitchTest.java
index 34d6a44..0e547af 100644
--- a/src/test/java21/com/android/tools/r8/jdk21/switchpatternmatching/EnumSwitchTest.java
+++ b/src/test/java21/com/android/tools/r8/jdk21/switchpatternmatching/EnumSwitchTest.java
@@ -16,8 +16,8 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.ToolHelper;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java21/com/android/tools/r8/jdk21/switchpatternmatching/EnumSwitchUsingEnumSwitchBootstrapMethodTest.java b/src/test/java21/com/android/tools/r8/jdk21/switchpatternmatching/EnumSwitchUsingEnumSwitchBootstrapMethodTest.java
index 41d5843..af5857d 100644
--- a/src/test/java21/com/android/tools/r8/jdk21/switchpatternmatching/EnumSwitchUsingEnumSwitchBootstrapMethodTest.java
+++ b/src/test/java21/com/android/tools/r8/jdk21/switchpatternmatching/EnumSwitchUsingEnumSwitchBootstrapMethodTest.java
@@ -13,8 +13,8 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.ToolHelper;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java21/com/android/tools/r8/jdk21/switchpatternmatching/StringSwitchTest.java b/src/test/java21/com/android/tools/r8/jdk21/switchpatternmatching/StringSwitchTest.java
index e227a6c..9fb3129 100644
--- a/src/test/java21/com/android/tools/r8/jdk21/switchpatternmatching/StringSwitchTest.java
+++ b/src/test/java21/com/android/tools/r8/jdk21/switchpatternmatching/StringSwitchTest.java
@@ -13,8 +13,8 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.ToolHelper;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java21/com/android/tools/r8/jdk21/switchpatternmatching/TypeSwitchTest.java b/src/test/java21/com/android/tools/r8/jdk21/switchpatternmatching/TypeSwitchTest.java
index e8b0da0..56fb2a5 100644
--- a/src/test/java21/com/android/tools/r8/jdk21/switchpatternmatching/TypeSwitchTest.java
+++ b/src/test/java21/com/android/tools/r8/jdk21/switchpatternmatching/TypeSwitchTest.java
@@ -13,8 +13,8 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.ToolHelper;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java25/com/android/tools/r8/jdk25/Java25ValidationTest.java b/src/test/java25/com/android/tools/r8/jdk25/Java25ValidationTest.java
index 7c1fb5c..0b0396a 100644
--- a/src/test/java25/com/android/tools/r8/jdk25/Java25ValidationTest.java
+++ b/src/test/java25/com/android/tools/r8/jdk25/Java25ValidationTest.java
@@ -13,7 +13,7 @@
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.cf.CfVersion;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.Path;
diff --git a/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/DexNumberValueSwitchTest.java b/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/DexNumberValueSwitchTest.java
index 9f9d2c1..8a1f24b 100644
--- a/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/DexNumberValueSwitchTest.java
+++ b/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/DexNumberValueSwitchTest.java
@@ -14,8 +14,8 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.ToolHelper;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/DexValueSwitchTest.java b/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/DexValueSwitchTest.java
index 633b792..8b22e4d 100644
--- a/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/DexValueSwitchTest.java
+++ b/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/DexValueSwitchTest.java
@@ -14,8 +14,8 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.ToolHelper;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/EnumLessCasesAtRuntimeSwitchTest.java b/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/EnumLessCasesAtRuntimeSwitchTest.java
index b24f759..98a1b1a 100644
--- a/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/EnumLessCasesAtRuntimeSwitchTest.java
+++ b/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/EnumLessCasesAtRuntimeSwitchTest.java
@@ -15,8 +15,8 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.ToolHelper;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/EnumMoreCasesAtRuntimeSwitchTest.java b/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/EnumMoreCasesAtRuntimeSwitchTest.java
index 578bc5f..7d14a7c 100644
--- a/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/EnumMoreCasesAtRuntimeSwitchTest.java
+++ b/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/EnumMoreCasesAtRuntimeSwitchTest.java
@@ -17,8 +17,8 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.ToolHelper;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/EnumSwitchOldSyntaxTest.java b/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/EnumSwitchOldSyntaxTest.java
index 95afb4f..4d3fec5 100644
--- a/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/EnumSwitchOldSyntaxTest.java
+++ b/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/EnumSwitchOldSyntaxTest.java
@@ -11,8 +11,8 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/EnumSwitchOldSyntaxV2Test.java b/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/EnumSwitchOldSyntaxV2Test.java
index 30fc275..1823fde 100644
--- a/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/EnumSwitchOldSyntaxV2Test.java
+++ b/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/EnumSwitchOldSyntaxV2Test.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/EnumSwitchTest.java b/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/EnumSwitchTest.java
index b2063b7..c2cae77 100644
--- a/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/EnumSwitchTest.java
+++ b/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/EnumSwitchTest.java
@@ -16,8 +16,8 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.ToolHelper;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/EnumSwitchUsingEnumSwitchBootstrapMethodTest.java b/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/EnumSwitchUsingEnumSwitchBootstrapMethodTest.java
index 4a30ba3..2f27d5e 100644
--- a/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/EnumSwitchUsingEnumSwitchBootstrapMethodTest.java
+++ b/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/EnumSwitchUsingEnumSwitchBootstrapMethodTest.java
@@ -13,8 +13,8 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.ToolHelper;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/StringSwitchOldSyntaxTest.java b/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/StringSwitchOldSyntaxTest.java
index c64ea5e..289cff3 100644
--- a/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/StringSwitchOldSyntaxTest.java
+++ b/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/StringSwitchOldSyntaxTest.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.TestParameters;
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/StringSwitchRegress382880986Test.java b/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/StringSwitchRegress382880986Test.java
index 6ad8e58..a29c9f7 100644
--- a/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/StringSwitchRegress382880986Test.java
+++ b/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/StringSwitchRegress382880986Test.java
@@ -12,8 +12,8 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.ToolHelper;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/StringSwitchTest.java b/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/StringSwitchTest.java
index 219391c..5ffdc20 100644
--- a/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/StringSwitchTest.java
+++ b/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/StringSwitchTest.java
@@ -13,8 +13,8 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.ToolHelper;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/TypeSwitchEnumAsClassTest.java b/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/TypeSwitchEnumAsClassTest.java
index df14fe2..b2dfcef 100644
--- a/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/TypeSwitchEnumAsClassTest.java
+++ b/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/TypeSwitchEnumAsClassTest.java
@@ -15,8 +15,8 @@
 import com.android.tools.r8.TestRunResult;
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.ToolHelper;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/TypeSwitchMissingClassTest.java b/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/TypeSwitchMissingClassTest.java
index 175bc9b..1bb9882 100644
--- a/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/TypeSwitchMissingClassTest.java
+++ b/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/TypeSwitchMissingClassTest.java
@@ -15,8 +15,8 @@
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.ToolHelper;
 import com.android.tools.r8.ToolHelper.DexVm.Version;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
diff --git a/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/TypeSwitchTest.java b/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/TypeSwitchTest.java
index 8258d20..85dc77c 100644
--- a/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/TypeSwitchTest.java
+++ b/src/test/java25/com/android/tools/r8/jdk25/switchpatternmatching/TypeSwitchTest.java
@@ -13,8 +13,8 @@
 import com.android.tools.r8.TestParametersCollection;
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.ToolHelper;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.Parameterized;
diff --git a/src/test/testbase/java/com/android/tools/r8/DesugarGraphTestConsumer.java b/src/test/testbase/java/com/android/tools/r8/DesugarGraphTestConsumer.java
index 2bd745d..12e5c34 100644
--- a/src/test/testbase/java/com/android/tools/r8/DesugarGraphTestConsumer.java
+++ b/src/test/testbase/java/com/android/tools/r8/DesugarGraphTestConsumer.java
@@ -9,9 +9,9 @@
 
 import com.android.tools.r8.origin.GlobalSyntheticOrigin;
 import com.android.tools.r8.origin.Origin;
-import com.android.tools.r8.utils.StringUtils;
-import com.android.tools.r8.utils.StringUtils.BraceType;
 import com.android.tools.r8.utils.collections.WorkList;
+import com.android.tools.r8.utils.internal.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils.BraceType;
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.HashSet;
diff --git a/src/test/testbase/java/com/android/tools/r8/DeviceRunner.java b/src/test/testbase/java/com/android/tools/r8/DeviceRunner.java
index fb46cfd..cf8668e 100644
--- a/src/test/testbase/java/com/android/tools/r8/DeviceRunner.java
+++ b/src/test/testbase/java/com/android/tools/r8/DeviceRunner.java
@@ -11,7 +11,7 @@
 import com.android.ddmlib.ShellCommandUnresponsiveException;
 import com.android.ddmlib.SyncException;
 import com.android.ddmlib.TimeoutException;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.base.Joiner;
 import java.io.BufferedReader;
 import java.io.ByteArrayOutputStream;
diff --git a/src/test/testbase/java/com/android/tools/r8/ExternalR8TestBuilder.java b/src/test/testbase/java/com/android/tools/r8/ExternalR8TestBuilder.java
index 42a3416..7979220 100644
--- a/src/test/testbase/java/com/android/tools/r8/ExternalR8TestBuilder.java
+++ b/src/test/testbase/java/com/android/tools/r8/ExternalR8TestBuilder.java
@@ -13,9 +13,9 @@
 import com.android.tools.r8.benchmarks.BenchmarkResults;
 import com.android.tools.r8.utils.AndroidApp;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.InternalOptions;
 import com.android.tools.r8.utils.ListUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unimplemented;
 import com.google.common.base.Charsets;
 import java.io.IOException;
diff --git a/src/test/testbase/java/com/android/tools/r8/JavaCompilerTool.java b/src/test/testbase/java/com/android/tools/r8/JavaCompilerTool.java
index ba23dd5..68a3dae 100644
--- a/src/test/testbase/java/com/android/tools/r8/JavaCompilerTool.java
+++ b/src/test/testbase/java/com/android/tools/r8/JavaCompilerTool.java
@@ -9,8 +9,8 @@
 
 import com.android.tools.r8.TestRuntime.CfRuntime;
 import com.android.tools.r8.ToolHelper.ProcessResult;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.ZipUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.Path;
diff --git a/src/test/testbase/java/com/android/tools/r8/JvmTestBuilder.java b/src/test/testbase/java/com/android/tools/r8/JvmTestBuilder.java
index 76f4e71..da583d6 100644
--- a/src/test/testbase/java/com/android/tools/r8/JvmTestBuilder.java
+++ b/src/test/testbase/java/com/android/tools/r8/JvmTestBuilder.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.testing.AndroidBuildVersion;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.AndroidApp;
-import com.android.tools.r8.utils.FileUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unimplemented;
 import com.google.common.collect.ObjectArrays;
 import java.io.IOException;
diff --git a/src/test/testbase/java/com/android/tools/r8/KotlinCompilerTool.java b/src/test/testbase/java/com/android/tools/r8/KotlinCompilerTool.java
index 6b80cae..69aa6ff 100644
--- a/src/test/testbase/java/com/android/tools/r8/KotlinCompilerTool.java
+++ b/src/test/testbase/java/com/android/tools/r8/KotlinCompilerTool.java
@@ -21,8 +21,8 @@
 import com.android.tools.r8.ToolHelper.CommandResultCache;
 import com.android.tools.r8.ToolHelper.ProcessResult;
 import com.android.tools.r8.utils.internal.ConsumerUtils;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.ThrowingConsumer;
 import com.android.tools.r8.utils.internal.collections.Pair;
 import com.android.tools.r8.utils.internal.exceptions.Unimplemented;
diff --git a/src/test/testbase/java/com/android/tools/r8/KotlinTestBase.java b/src/test/testbase/java/com/android/tools/r8/KotlinTestBase.java
index 893d0f2..1546804 100644
--- a/src/test/testbase/java/com/android/tools/r8/KotlinTestBase.java
+++ b/src/test/testbase/java/com/android/tools/r8/KotlinTestBase.java
@@ -11,7 +11,7 @@
 import com.android.tools.r8.KotlinCompilerTool.KotlinTargetVersion;
 import com.android.tools.r8.TestRuntime.CfRuntime;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.FileUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.android.tools.r8.utils.internal.SemanticVersion;
 import java.io.IOException;
 import java.nio.file.Files;
diff --git a/src/test/testbase/java/com/android/tools/r8/L8TestBuilder.java b/src/test/testbase/java/com/android/tools/r8/L8TestBuilder.java
index 7cfc898..36ed12f 100644
--- a/src/test/testbase/java/com/android/tools/r8/L8TestBuilder.java
+++ b/src/test/testbase/java/com/android/tools/r8/L8TestBuilder.java
@@ -18,9 +18,9 @@
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.AndroidAppConsumers;
-import com.android.tools.r8.utils.internal.ConsumerUtils;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.InternalOptions;
+import com.android.tools.r8.utils.internal.ConsumerUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.nio.charset.StandardCharsets;
diff --git a/src/test/testbase/java/com/android/tools/r8/L8TestCompileResult.java b/src/test/testbase/java/com/android/tools/r8/L8TestCompileResult.java
index d4a599a..8f0387b 100644
--- a/src/test/testbase/java/com/android/tools/r8/L8TestCompileResult.java
+++ b/src/test/testbase/java/com/android/tools/r8/L8TestCompileResult.java
@@ -9,9 +9,9 @@
 import com.android.tools.r8.ToolHelper.ProcessResult;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.AndroidApp;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.internal.ThrowingConsumer;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.ThrowingConsumer;
 import com.android.tools.r8.utils.internal.exceptions.Unimplemented;
 import java.io.IOException;
 import java.nio.file.Files;
diff --git a/src/test/testbase/java/com/android/tools/r8/MarkerMatcher.java b/src/test/testbase/java/com/android/tools/r8/MarkerMatcher.java
index b22c728..f378a9b 100644
--- a/src/test/testbase/java/com/android/tools/r8/MarkerMatcher.java
+++ b/src/test/testbase/java/com/android/tools/r8/MarkerMatcher.java
@@ -10,7 +10,7 @@
 import com.android.tools.r8.dex.Marker;
 import com.android.tools.r8.dex.Marker.Tool;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.util.Collection;
 import org.hamcrest.Description;
diff --git a/src/test/testbase/java/com/android/tools/r8/ProguardTestBuilder.java b/src/test/testbase/java/com/android/tools/r8/ProguardTestBuilder.java
index 652cf7d..33b8a81 100644
--- a/src/test/testbase/java/com/android/tools/r8/ProguardTestBuilder.java
+++ b/src/test/testbase/java/com/android/tools/r8/ProguardTestBuilder.java
@@ -8,8 +8,8 @@
 import com.android.tools.r8.ToolHelper.ProcessResult;
 import com.android.tools.r8.benchmarks.BenchmarkResults;
 import com.android.tools.r8.utils.AndroidApp;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.InternalOptions;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unimplemented;
 import com.google.common.base.Charsets;
 import java.io.IOException;
diff --git a/src/test/testbase/java/com/android/tools/r8/R8RunArtTestsTest.java b/src/test/testbase/java/com/android/tools/r8/R8RunArtTestsTest.java
index f60b838..de7b095 100644
--- a/src/test/testbase/java/com/android/tools/r8/R8RunArtTestsTest.java
+++ b/src/test/testbase/java/com/android/tools/r8/R8RunArtTestsTest.java
@@ -19,12 +19,12 @@
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.ArtErrorParser;
 import com.android.tools.r8.utils.ArtErrorParser.ArtErrorInfo;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.InternalOptions;
 import com.android.tools.r8.utils.InternalOptions.LineNumberOptimization;
 import com.android.tools.r8.utils.ListUtils;
 import com.android.tools.r8.utils.TestDescriptionWatcher;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.base.Charsets;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableListMultimap;
diff --git a/src/test/testbase/java/com/android/tools/r8/R8TestBuilder.java b/src/test/testbase/java/com/android/tools/r8/R8TestBuilder.java
index 927b707..3aeed0b 100644
--- a/src/test/testbase/java/com/android/tools/r8/R8TestBuilder.java
+++ b/src/test/testbase/java/com/android/tools/r8/R8TestBuilder.java
@@ -42,15 +42,15 @@
 import com.android.tools.r8.tracereferences.TraceReferencesNativeReferencesConsumer;
 import com.android.tools.r8.utils.AndroidApp;
 import com.android.tools.r8.utils.ArchiveResourceProvider;
-import com.android.tools.r8.utils.internal.Box;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.InternalOptions;
 import com.android.tools.r8.utils.MapIdTemplateProvider;
-import com.android.tools.r8.utils.internal.OptionalBool;
-import com.android.tools.r8.utils.internal.SemanticVersion;
 import com.android.tools.r8.utils.SourceFileTemplateProvider;
 import com.android.tools.r8.utils.ZipUtils;
 import com.android.tools.r8.utils.codeinspector.Matchers;
+import com.android.tools.r8.utils.internal.Box;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.OptionalBool;
+import com.android.tools.r8.utils.internal.SemanticVersion;
 import com.android.tools.r8.utils.internal.collections.Pair;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import java.io.ByteArrayInputStream;
diff --git a/src/test/testbase/java/com/android/tools/r8/R8TestCompileResultBase.java b/src/test/testbase/java/com/android/tools/r8/R8TestCompileResultBase.java
index 9db2809..673eb16 100644
--- a/src/test/testbase/java/com/android/tools/r8/R8TestCompileResultBase.java
+++ b/src/test/testbase/java/com/android/tools/r8/R8TestCompileResultBase.java
@@ -29,15 +29,15 @@
 import com.android.tools.r8.shaking.ProguardConfigurationRule;
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
 import com.android.tools.r8.utils.AndroidApp;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.InternalOptions;
-import com.android.tools.r8.utils.internal.ThrowingBiConsumer;
-import com.android.tools.r8.utils.internal.ThrowingConsumer;
 import com.android.tools.r8.utils.ZipUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FoundClassSubject;
 import com.android.tools.r8.utils.graphinspector.GraphInspector;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.ThrowingBiConsumer;
+import com.android.tools.r8.utils.internal.ThrowingConsumer;
 import it.unimi.dsi.fastutil.ints.Int2ReferenceLinkedOpenHashMap;
 import it.unimi.dsi.fastutil.ints.Int2ReferenceMap;
 import java.io.IOException;
diff --git a/src/test/testbase/java/com/android/tools/r8/SingleTestRunResult.java b/src/test/testbase/java/com/android/tools/r8/SingleTestRunResult.java
index 8b1a9ef..6feda79 100644
--- a/src/test/testbase/java/com/android/tools/r8/SingleTestRunResult.java
+++ b/src/test/testbase/java/com/android/tools/r8/SingleTestRunResult.java
@@ -14,9 +14,9 @@
 import com.android.tools.r8.naming.retrace.StackTrace;
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
 import com.android.tools.r8.utils.AndroidApp;
-import com.android.tools.r8.utils.StringUtils;
-import com.android.tools.r8.utils.internal.ThrowingConsumer;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
+import com.android.tools.r8.utils.internal.ThrowingConsumer;
 import java.io.IOException;
 import java.io.PrintStream;
 import java.nio.file.Path;
diff --git a/src/test/testbase/java/com/android/tools/r8/TestBase.java b/src/test/testbase/java/com/android/tools/r8/TestBase.java
index 05e4146..360b79c 100644
--- a/src/test/testbase/java/com/android/tools/r8/TestBase.java
+++ b/src/test/testbase/java/com/android/tools/r8/TestBase.java
@@ -85,7 +85,6 @@
 import com.android.tools.r8.utils.ListUtils;
 import com.android.tools.r8.utils.PreloadedClassFileProvider;
 import com.android.tools.r8.utils.Reporter;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.TestDescriptionWatcher;
 import com.android.tools.r8.utils.ZipUtils.ZipBuilder;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
@@ -93,6 +92,7 @@
 import com.android.tools.r8.utils.codeinspector.FoundClassSubject;
 import com.android.tools.r8.utils.codeinspector.FoundMethodSubject;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.collections.Pair;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import com.android.tools.r8.utils.timing.Timing;
diff --git a/src/test/testbase/java/com/android/tools/r8/TestCompileResult.java b/src/test/testbase/java/com/android/tools/r8/TestCompileResult.java
index 762a070..becf7a5 100644
--- a/src/test/testbase/java/com/android/tools/r8/TestCompileResult.java
+++ b/src/test/testbase/java/com/android/tools/r8/TestCompileResult.java
@@ -26,14 +26,14 @@
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.AndroidApp;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.InternalOptions;
-import com.android.tools.r8.utils.internal.ThrowingBiConsumer;
-import com.android.tools.r8.utils.internal.ThrowingConsumer;
-import com.android.tools.r8.utils.internal.TriFunction;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.Matchers;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.ThrowingBiConsumer;
+import com.android.tools.r8.utils.internal.ThrowingConsumer;
+import com.android.tools.r8.utils.internal.TriFunction;
 import com.android.tools.r8.utils.internal.exceptions.Unimplemented;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import com.google.common.collect.ImmutableList;
diff --git a/src/test/testbase/java/com/android/tools/r8/TestRunResult.java b/src/test/testbase/java/com/android/tools/r8/TestRunResult.java
index 0614db0..89fd1a2 100644
--- a/src/test/testbase/java/com/android/tools/r8/TestRunResult.java
+++ b/src/test/testbase/java/com/android/tools/r8/TestRunResult.java
@@ -7,9 +7,9 @@
 import static org.hamcrest.CoreMatchers.containsString;
 import static org.hamcrest.CoreMatchers.is;
 
-import com.android.tools.r8.utils.StringUtils;
-import com.android.tools.r8.utils.internal.ThrowingConsumer;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
+import com.android.tools.r8.utils.internal.StringUtils;
+import com.android.tools.r8.utils.internal.ThrowingConsumer;
 import java.io.IOException;
 import java.util.Arrays;
 import java.util.List;
diff --git a/src/test/testbase/java/com/android/tools/r8/TestRuntime.java b/src/test/testbase/java/com/android/tools/r8/TestRuntime.java
index 1b409dd..719eb38 100644
--- a/src/test/testbase/java/com/android/tools/r8/TestRuntime.java
+++ b/src/test/testbase/java/com/android/tools/r8/TestRuntime.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.ToolHelper.DexVm;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.ListUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unimplemented;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import com.android.tools.r8.utils.structural.Ordered;
diff --git a/src/test/testbase/java/com/android/tools/r8/TestShrinkerBuilder.java b/src/test/testbase/java/com/android/tools/r8/TestShrinkerBuilder.java
index 50ec7cb..bed4bd5 100644
--- a/src/test/testbase/java/com/android/tools/r8/TestShrinkerBuilder.java
+++ b/src/test/testbase/java/com/android/tools/r8/TestShrinkerBuilder.java
@@ -15,8 +15,8 @@
 import com.android.tools.r8.references.TypeReference;
 import com.android.tools.r8.shaking.ProguardKeepAttributes;
 import com.android.tools.r8.utils.AndroidApiLevel;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Sets;
 import java.io.IOException;
diff --git a/src/test/testbase/java/com/android/tools/r8/ToolHelper.java b/src/test/testbase/java/com/android/tools/r8/ToolHelper.java
index 8c2f7f7..0e23181 100644
--- a/src/test/testbase/java/com/android/tools/r8/ToolHelper.java
+++ b/src/test/testbase/java/com/android/tools/r8/ToolHelper.java
@@ -6,9 +6,9 @@
 import static com.android.tools.r8.ToolHelper.TestDataSourceSet.computeLegacyOrGradleSpecifiedLocation;
 import static com.android.tools.r8.utils.DexVersion.V39;
 import static com.android.tools.r8.utils.DexVersion.V41;
-import static com.android.tools.r8.utils.FileUtils.CLASS_EXTENSION;
-import static com.android.tools.r8.utils.FileUtils.JAVA_EXTENSION;
-import static com.android.tools.r8.utils.FileUtils.isDexFile;
+import static com.android.tools.r8.utils.internal.FileUtils.CLASS_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.JAVA_EXTENSION;
+import static com.android.tools.r8.utils.internal.FileUtils.isDexFile;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.fail;
@@ -41,12 +41,12 @@
 import com.android.tools.r8.utils.AndroidAppConsumers;
 import com.android.tools.r8.utils.DexVersion;
 import com.android.tools.r8.utils.ExceptionUtils;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.InternalOptions;
 import com.android.tools.r8.utils.ListUtils;
 import com.android.tools.r8.utils.Reporter;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.ZipUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.collections.Pair;
 import com.android.tools.r8.utils.internal.exceptions.Unimplemented;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
diff --git a/src/test/testbase/java/com/android/tools/r8/androidresources/AndroidResourceTestingUtils.java b/src/test/testbase/java/com/android/tools/r8/androidresources/AndroidResourceTestingUtils.java
index be16f60..4541cf1 100644
--- a/src/test/testbase/java/com/android/tools/r8/androidresources/AndroidResourceTestingUtils.java
+++ b/src/test/testbase/java/com/android/tools/r8/androidresources/AndroidResourceTestingUtils.java
@@ -22,10 +22,10 @@
 import com.android.tools.r8.transformers.MethodTransformer;
 import com.android.tools.r8.utils.AndroidApiLevel;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.FileUtils;
-import com.android.tools.r8.utils.internal.StreamUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.ZipUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StreamUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Lists;
 import com.google.common.collect.MoreCollectors;
diff --git a/src/test/testbase/java/com/android/tools/r8/benchmarks/BenchmarkResults.java b/src/test/testbase/java/com/android/tools/r8/benchmarks/BenchmarkResults.java
index 92cfd22..e3c7bc6 100644
--- a/src/test/testbase/java/com/android/tools/r8/benchmarks/BenchmarkResults.java
+++ b/src/test/testbase/java/com/android/tools/r8/benchmarks/BenchmarkResults.java
@@ -4,7 +4,7 @@
 package com.android.tools.r8.benchmarks;
 
 import com.android.tools.r8.DexSegments.SegmentInfo;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import it.unimi.dsi.fastutil.ints.Int2ReferenceMap;
 import java.io.IOException;
 import java.nio.file.Path;
diff --git a/src/test/testbase/java/com/android/tools/r8/desugar/desugaredlibrary/test/DesugaredLibraryTestBuilder.java b/src/test/testbase/java/com/android/tools/r8/desugar/desugaredlibrary/test/DesugaredLibraryTestBuilder.java
index 25218fc..e5da849 100644
--- a/src/test/testbase/java/com/android/tools/r8/desugar/desugaredlibrary/test/DesugaredLibraryTestBuilder.java
+++ b/src/test/testbase/java/com/android/tools/r8/desugar/desugaredlibrary/test/DesugaredLibraryTestBuilder.java
@@ -35,11 +35,11 @@
 import com.android.tools.r8.profile.art.model.ExternalArtProfile;
 import com.android.tools.r8.profile.art.utils.ArtProfileTestingUtils;
 import com.android.tools.r8.tracereferences.TraceReferences;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.InternalOptions;
-import com.android.tools.r8.utils.StringUtils;
-import com.android.tools.r8.utils.internal.ThrowingConsumer;
 import com.android.tools.r8.utils.codeinspector.VerticallyMergedClassesInspector;
+import com.android.tools.r8.utils.internal.FileUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
+import com.android.tools.r8.utils.internal.ThrowingConsumer;
 import com.google.common.base.Charsets;
 import java.io.IOException;
 import java.nio.file.Path;
diff --git a/src/test/testbase/java/com/android/tools/r8/enumunboxing/EnumUnboxingTestBase.java b/src/test/testbase/java/com/android/tools/r8/enumunboxing/EnumUnboxingTestBase.java
index ea6fb15..e74252e 100644
--- a/src/test/testbase/java/com/android/tools/r8/enumunboxing/EnumUnboxingTestBase.java
+++ b/src/test/testbase/java/com/android/tools/r8/enumunboxing/EnumUnboxingTestBase.java
@@ -8,9 +8,9 @@
 
 import com.android.tools.r8.TestBase;
 import com.android.tools.r8.TestParametersCollection;
-import com.android.tools.r8.utils.internal.BooleanUtils;
 import com.android.tools.r8.utils.InternalOptions;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.BooleanUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.List;
 
 public class EnumUnboxingTestBase extends TestBase {
diff --git a/src/test/testbase/java/com/android/tools/r8/jasmin/JasminBuilder.java b/src/test/testbase/java/com/android/tools/r8/jasmin/JasminBuilder.java
index 0eb25e9..4e3aa7f 100644
--- a/src/test/testbase/java/com/android/tools/r8/jasmin/JasminBuilder.java
+++ b/src/test/testbase/java/com/android/tools/r8/jasmin/JasminBuilder.java
@@ -19,8 +19,8 @@
 import com.android.tools.r8.utils.AndroidApp;
 import com.android.tools.r8.utils.DescriptorUtils;
 import com.android.tools.r8.utils.InternalOptions;
-import com.android.tools.r8.utils.StringUtils;
-import com.android.tools.r8.utils.StringUtils.BraceType;
+import com.android.tools.r8.utils.internal.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils.BraceType;
 import com.android.tools.r8.utils.timing.Timing;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Iterables;
diff --git a/src/test/testbase/java/com/android/tools/r8/keepanno/KeepAnnoTestUtils.java b/src/test/testbase/java/com/android/tools/r8/keepanno/KeepAnnoTestUtils.java
index 8a47c3a..3c6162f 100644
--- a/src/test/testbase/java/com/android/tools/r8/keepanno/KeepAnnoTestUtils.java
+++ b/src/test/testbase/java/com/android/tools/r8/keepanno/KeepAnnoTestUtils.java
@@ -5,9 +5,9 @@
 package com.android.tools.r8.keepanno;
 
 import static com.android.tools.r8.R8TestBuilder.KeepAnnotationLibrary.ANDROIDX;
-import static com.android.tools.r8.utils.FileUtils.isClassFile;
-import static com.android.tools.r8.utils.FileUtils.isJarFile;
-import static com.android.tools.r8.utils.FileUtils.isZipFile;
+import static com.android.tools.r8.utils.internal.FileUtils.isClassFile;
+import static com.android.tools.r8.utils.internal.FileUtils.isJarFile;
+import static com.android.tools.r8.utils.internal.FileUtils.isZipFile;
 import static org.junit.Assert.assertTrue;
 
 import com.android.tools.r8.ByteDataView;
@@ -19,9 +19,9 @@
 import com.android.tools.r8.keepanno.ast.KeepDeclaration;
 import com.android.tools.r8.keepanno.keeprules.KeepRuleExtractor;
 import com.android.tools.r8.keepanno.keeprules.KeepRuleExtractorOptions;
-import com.android.tools.r8.utils.FileUtils;
 import com.android.tools.r8.utils.ListUtils;
 import com.android.tools.r8.utils.ZipUtils;
+import com.android.tools.r8.utils.internal.FileUtils;
 import com.google.common.collect.ImmutableList;
 import com.google.common.io.ByteStreams;
 import java.io.IOException;
diff --git a/src/test/testbase/java/com/android/tools/r8/naming/retrace/StackTrace.java b/src/test/testbase/java/com/android/tools/r8/naming/retrace/StackTrace.java
index 30b1b4d..3ac0070 100644
--- a/src/test/testbase/java/com/android/tools/r8/naming/retrace/StackTrace.java
+++ b/src/test/testbase/java/com/android/tools/r8/naming/retrace/StackTrace.java
@@ -17,7 +17,7 @@
 import com.android.tools.r8.retrace.Retrace;
 import com.android.tools.r8.retrace.RetraceCommand;
 import com.android.tools.r8.utils.internal.Box;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.base.Equivalence;
 import java.util.ArrayList;
 import java.util.List;
diff --git a/src/test/testbase/java/com/android/tools/r8/profile/art/model/ExternalArtProfile.java b/src/test/testbase/java/com/android/tools/r8/profile/art/model/ExternalArtProfile.java
index 76cb37b..d4f5638 100644
--- a/src/test/testbase/java/com/android/tools/r8/profile/art/model/ExternalArtProfile.java
+++ b/src/test/testbase/java/com/android/tools/r8/profile/art/model/ExternalArtProfile.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.profile.art.ArtProfileMethodRuleInfoImpl;
 import com.android.tools.r8.references.ClassReference;
 import com.android.tools.r8.references.MethodReference;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.LinkedHashMap;
 import java.util.Map;
 import java.util.function.Consumer;
diff --git a/src/test/testbase/java/com/android/tools/r8/smali/SmaliBuilder.java b/src/test/testbase/java/com/android/tools/r8/smali/SmaliBuilder.java
index 0a2c7ab..5af6496 100644
--- a/src/test/testbase/java/com/android/tools/r8/smali/SmaliBuilder.java
+++ b/src/test/testbase/java/com/android/tools/r8/smali/SmaliBuilder.java
@@ -8,7 +8,7 @@
 import com.android.tools.r8.utils.AndroidApp;
 import com.android.tools.r8.utils.DescriptorUtils;
 import com.android.tools.r8.utils.Smali;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.ImmutableList;
 import java.io.IOException;
 import java.util.ArrayList;
diff --git a/src/test/testbase/java/com/android/tools/r8/transformers/ClassFileTransformer.java b/src/test/testbase/java/com/android/tools/r8/transformers/ClassFileTransformer.java
index d2c4923..282f3ff 100644
--- a/src/test/testbase/java/com/android/tools/r8/transformers/ClassFileTransformer.java
+++ b/src/test/testbase/java/com/android/tools/r8/transformers/ClassFileTransformer.java
@@ -6,7 +6,7 @@
 import static com.android.tools.r8.references.Reference.classFromTypeName;
 import static com.android.tools.r8.utils.DescriptorUtils.getBinaryNameFromDescriptor;
 import static com.android.tools.r8.utils.InternalOptions.ASM_VERSION;
-import static com.android.tools.r8.utils.StringUtils.replaceAll;
+import static com.android.tools.r8.utils.internal.StringUtils.replaceAll;
 
 import com.android.tools.r8.TestRuntime.CfVm;
 import com.android.tools.r8.ToolHelper;
diff --git a/src/test/testbase/java/com/android/tools/r8/utils/ArtErrorParser.java b/src/test/testbase/java/com/android/tools/r8/utils/ArtErrorParser.java
index 5f00fc9..da7c474 100644
--- a/src/test/testbase/java/com/android/tools/r8/utils/ArtErrorParser.java
+++ b/src/test/testbase/java/com/android/tools/r8/utils/ArtErrorParser.java
@@ -7,6 +7,7 @@
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.MethodSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.ArrayList;
 import java.util.List;
 
diff --git a/src/test/testbase/java/com/android/tools/r8/utils/Smali.java b/src/test/testbase/java/com/android/tools/r8/utils/Smali.java
index 46c8e83..c4a5f14 100644
--- a/src/test/testbase/java/com/android/tools/r8/utils/Smali.java
+++ b/src/test/testbase/java/com/android/tools/r8/utils/Smali.java
@@ -13,6 +13,7 @@
 import com.android.tools.r8.graph.DexApplication;
 import com.android.tools.r8.origin.Origin;
 import com.android.tools.r8.synthesis.SyntheticItems.GlobalSyntheticsStrategy;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.timing.Timing;
 import com.android.tools.smali.dexlib2.Opcodes;
 import com.android.tools.smali.dexlib2.writer.builder.DexBuilder;
diff --git a/src/test/testbase/java/com/android/tools/r8/utils/codeinspector/AnnotationMatchers.java b/src/test/testbase/java/com/android/tools/r8/utils/codeinspector/AnnotationMatchers.java
index 392a506..b89f60c 100644
--- a/src/test/testbase/java/com/android/tools/r8/utils/codeinspector/AnnotationMatchers.java
+++ b/src/test/testbase/java/com/android/tools/r8/utils/codeinspector/AnnotationMatchers.java
@@ -5,7 +5,7 @@
 package com.android.tools.r8.utils.codeinspector;
 
 import com.android.tools.r8.graph.DexAnnotationElement;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.collections.Pair;
 import java.util.Arrays;
 import java.util.List;
diff --git a/src/test/testbase/java/com/android/tools/r8/utils/codeinspector/FoundClassSubject.java b/src/test/testbase/java/com/android/tools/r8/utils/codeinspector/FoundClassSubject.java
index 63dfcdb..46b8ea3 100644
--- a/src/test/testbase/java/com/android/tools/r8/utils/codeinspector/FoundClassSubject.java
+++ b/src/test/testbase/java/com/android/tools/r8/utils/codeinspector/FoundClassSubject.java
@@ -46,9 +46,9 @@
 import com.android.tools.r8.retrace.Retracer;
 import com.android.tools.r8.synthesis.SyntheticItemsTestUtils;
 import com.android.tools.r8.utils.DescriptorUtils;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.ZipUtils;
 import com.android.tools.r8.utils.codeinspector.CodeInspector.MappingWrapper;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.Sets;
 import java.io.File;
 import java.nio.file.Paths;
diff --git a/src/test/testbase/java/com/android/tools/r8/utils/codeinspector/FoundMethodSubject.java b/src/test/testbase/java/com/android/tools/r8/utils/codeinspector/FoundMethodSubject.java
index 09bf61a..5f186e8 100644
--- a/src/test/testbase/java/com/android/tools/r8/utils/codeinspector/FoundMethodSubject.java
+++ b/src/test/testbase/java/com/android/tools/r8/utils/codeinspector/FoundMethodSubject.java
@@ -39,8 +39,8 @@
 import com.android.tools.r8.references.Reference;
 import com.android.tools.r8.references.TypeReference;
 import com.android.tools.r8.synthesis.SyntheticItems.GlobalSyntheticsStrategy;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.LocalVariableTable.LocalVariableTableEntry;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unimplemented;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import com.google.common.base.Predicates;
diff --git a/src/test/testbase/java/com/android/tools/r8/utils/codeinspector/HorizontallyMergedClassesInspector.java b/src/test/testbase/java/com/android/tools/r8/utils/codeinspector/HorizontallyMergedClassesInspector.java
index 04663af..d8a8e84 100644
--- a/src/test/testbase/java/com/android/tools/r8/utils/codeinspector/HorizontallyMergedClassesInspector.java
+++ b/src/test/testbase/java/com/android/tools/r8/utils/codeinspector/HorizontallyMergedClassesInspector.java
@@ -21,7 +21,7 @@
 import com.android.tools.r8.repackaging.RepackagingLens;
 import com.android.tools.r8.utils.ClassReferenceUtils;
 import com.android.tools.r8.utils.SetUtils;
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.Sets;
 import java.util.Arrays;
 import java.util.Collection;
diff --git a/src/test/testbase/java/com/android/tools/r8/utils/codeinspector/Main.java b/src/test/testbase/java/com/android/tools/r8/utils/codeinspector/Main.java
index 63a6033..aada528 100644
--- a/src/test/testbase/java/com/android/tools/r8/utils/codeinspector/Main.java
+++ b/src/test/testbase/java/com/android/tools/r8/utils/codeinspector/Main.java
@@ -3,7 +3,7 @@
 // BSD-style license that can be found in the LICENSE file.
 package com.android.tools.r8.utils.codeinspector;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.io.IOException;
 import java.nio.file.Path;
 import java.nio.file.Paths;
diff --git a/src/test/testbase/java/com/android/tools/r8/utils/codeinspector/MethodMatchers.java b/src/test/testbase/java/com/android/tools/r8/utils/codeinspector/MethodMatchers.java
index 8d7e78b..01b3e50 100644
--- a/src/test/testbase/java/com/android/tools/r8/utils/codeinspector/MethodMatchers.java
+++ b/src/test/testbase/java/com/android/tools/r8/utils/codeinspector/MethodMatchers.java
@@ -6,7 +6,7 @@
 
 import static junit.framework.TestCase.assertEquals;
 
-import com.android.tools.r8.utils.StringUtils;
+import com.android.tools.r8.utils.internal.StringUtils;
 import java.util.Arrays;
 import java.util.List;
 import org.hamcrest.Description;
diff --git a/src/test/testbase/java/com/android/tools/r8/utils/codeinspector/analysis/ProtoApplicationStats.java b/src/test/testbase/java/com/android/tools/r8/utils/codeinspector/analysis/ProtoApplicationStats.java
index 73ca25e..6202b0c 100644
--- a/src/test/testbase/java/com/android/tools/r8/utils/codeinspector/analysis/ProtoApplicationStats.java
+++ b/src/test/testbase/java/com/android/tools/r8/utils/codeinspector/analysis/ProtoApplicationStats.java
@@ -8,7 +8,6 @@
 import com.android.tools.r8.graph.DexItemFactory;
 import com.android.tools.r8.graph.DexMethod;
 import com.android.tools.r8.graph.DexType;
-import com.android.tools.r8.utils.StringUtils;
 import com.android.tools.r8.utils.codeinspector.ClassSubject;
 import com.android.tools.r8.utils.codeinspector.CodeInspector;
 import com.android.tools.r8.utils.codeinspector.FieldSubject;
@@ -16,6 +15,7 @@
 import com.android.tools.r8.utils.codeinspector.FoundFieldSubject;
 import com.android.tools.r8.utils.codeinspector.FoundMethodSubject;
 import com.android.tools.r8.utils.codeinspector.InstructionSubject;
+import com.android.tools.r8.utils.internal.StringUtils;
 import com.google.common.collect.Sets;
 import java.util.Set;
 import java.util.function.Function;
diff --git a/src/main/java/com/android/tools/r8/utils/FileUtils.java b/src/utils/java/com/android/tools/r8/utils/internal/FileUtils.java
similarity index 91%
rename from src/main/java/com/android/tools/r8/utils/FileUtils.java
rename to src/utils/java/com/android/tools/r8/utils/internal/FileUtils.java
index d8c3b62..da570e2 100644
--- a/src/main/java/com/android/tools/r8/utils/FileUtils.java
+++ b/src/utils/java/com/android/tools/r8/utils/internal/FileUtils.java
@@ -1,9 +1,8 @@
 // Copyright (c) 2017, the R8 project authors. Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
-package com.android.tools.r8.utils;
+package com.android.tools.r8.utils.internal;
 
-import com.android.tools.r8.ByteDataView;
 import com.google.common.io.Closer;
 import java.io.File;
 import java.io.IOException;
@@ -17,6 +16,7 @@
 import java.nio.file.StandardOpenOption;
 import java.util.Arrays;
 import java.util.List;
+import java.util.function.Consumer;
 import java.util.zip.ZipFile;
 
 public class FileUtils {
@@ -149,32 +149,26 @@
     return file;
   }
 
-  public static Path validateOutputFile(Path path, Reporter reporter) {
+  public static Path validateOutputFile(Path path, Consumer<String> errorConsumer) {
     if (path != null) {
       if (!isJarOrZipFile(path) && !(Files.exists(path) && Files.isDirectory(path))) {
-        reporter.error(new StringDiagnostic(
+        errorConsumer.accept(
             "Invalid output: "
                 + path
-                + "\nOutput must be a .zip or .jar archive or an existing directory"));
+                + "\nOutput must be a .zip or .jar archive or an existing directory");
       }
     }
     return path;
   }
 
-  public static OutputStream openPath(
-      Closer closer,
-      Path file,
-      OpenOption... openOptions)
+  public static OutputStream openPath(Closer closer, Path file, OpenOption... openOptions)
       throws IOException {
     assert file != null;
     return openPathWithDefault(closer, file, null, openOptions);
   }
 
   public static OutputStream openPathWithDefault(
-      Closer closer,
-      Path file,
-      OutputStream defaultOutput,
-      OpenOption... openOptions)
+      Closer closer, Path file, OutputStream defaultOutput, OpenOption... openOptions)
       throws IOException {
     OutputStream mapOut;
     if (file == null) {
@@ -214,21 +208,22 @@
 
   public static void writeToFile(Path output, OutputStream defValue, byte[] contents)
       throws IOException {
-    writeToFile(output, defValue, ByteDataView.of(contents));
+    writeToFile(output, defValue, contents, 0, contents.length);
   }
 
-  public static void writeToFile(Path output, OutputStream defValue, ByteDataView contents)
+  public static void writeToFile(
+      Path output, OutputStream defValue, byte[] contents, int offset, int length)
       throws IOException {
     try (Closer closer = Closer.create()) {
       OutputStream outputStream =
-          openPathWithDefault(
+          FileUtils.openPathWithDefault(
               closer,
               output,
               defValue,
               StandardOpenOption.CREATE,
               StandardOpenOption.TRUNCATE_EXISTING,
               StandardOpenOption.WRITE);
-      outputStream.write(contents.getBuffer(), contents.getOffset(), contents.getLength());
+      outputStream.write(contents, offset, length);
     }
   }
 
diff --git a/src/main/java/com/android/tools/r8/utils/StringUtils.java b/src/utils/java/com/android/tools/r8/utils/internal/StringUtils.java
similarity index 94%
rename from src/main/java/com/android/tools/r8/utils/StringUtils.java
rename to src/utils/java/com/android/tools/r8/utils/internal/StringUtils.java
index e7d886d..c6e0b40 100644
--- a/src/main/java/com/android/tools/r8/utils/StringUtils.java
+++ b/src/utils/java/com/android/tools/r8/utils/internal/StringUtils.java
@@ -1,10 +1,8 @@
 // Copyright (c) 2016, the R8 project authors. Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
-package com.android.tools.r8.utils;
+package com.android.tools.r8.utils.internal;
 
-import com.android.tools.r8.utils.internal.IntBox;
-import com.android.tools.r8.utils.internal.IterableUtils;
 import com.android.tools.r8.utils.internal.exceptions.Unreachable;
 import java.io.PrintWriter;
 import java.io.StringWriter;
@@ -41,21 +39,31 @@
 
     public String left() {
       switch (this) {
-        case PARENS: return "(";
-        case SQUARE: return "[";
-        case TUBORG: return "{";
-        case NONE: return "";
-        default: throw new Unreachable("Invalid brace type: " + this);
+        case PARENS:
+          return "(";
+        case SQUARE:
+          return "[";
+        case TUBORG:
+          return "{";
+        case NONE:
+          return "";
+        default:
+          throw new Unreachable("Invalid brace type: " + this);
       }
     }
 
     public String right() {
       switch (this) {
-        case PARENS: return ")";
-        case SQUARE: return "]";
-        case TUBORG: return "}";
-        case NONE: return "";
-        default: throw new Unreachable("Invalid brace type: " + this);
+        case PARENS:
+          return ")";
+        case SQUARE:
+          return "]";
+        case TUBORG:
+          return "}";
+        case NONE:
+          return "";
+        default:
+          throw new Unreachable("Invalid brace type: " + this);
       }
     }
   }
@@ -64,7 +72,7 @@
     StringBuilder builder = new StringBuilder();
     for (int i = 0; i < s.length(); i++) {
       char ch = s.charAt(i);
-      if (0x1f < ch && ch < 0x7f) {  // 0 - 0x1f and 0x7f are control characters.
+      if (0x1f < ch && ch < 0x7f) { // 0 - 0x1f and 0x7f are control characters.
         builder.append(ch);
       } else {
         builder.append("\\u").append(StringUtils.hexString(ch, 4, false));
@@ -324,7 +332,7 @@
 
   private static String zeroPrefixString(String s, int width) {
     String prefix = "0000000000000000";
-    assert(width <= prefix.length());
+    assert width <= prefix.length();
     int prefixLength = width - s.length();
     if (prefixLength > 0) {
       StringBuilder builder = new StringBuilder();
@@ -341,14 +349,14 @@
   }
 
   public static String hexString(int value, int width, boolean zeroXPrefix) {
-    assert(0 <= width && width <= 8);
+    assert 0 <= width && width <= 8;
     String prefix = zeroXPrefix ? "0x" : "";
     String hex = Integer.toHexString(value);
     if (value >= 0) {
       return prefix + zeroPrefixString(hex, width);
     } else {
       // Negative ints are always formatted as 8 characters.
-      assert(hex.length() == 8);
+      assert hex.length() == 8;
       return prefix + hex;
     }
   }
@@ -358,14 +366,14 @@
   }
 
   public static String hexString(long value, int width, boolean zeroXPrefix) {
-    assert(0 <= width && width <= 16);
+    assert 0 <= width && width <= 16;
     String prefix = zeroXPrefix ? "0x" : "";
     String hex = Long.toHexString(value);
     if (value >= 0) {
       return prefix + zeroPrefixString(hex, width);
     } else {
       // Negative longs are always formatted as 16 characters.
-      assert(hex.length() == 16);
+      assert hex.length() == 16;
       return prefix + hex;
     }
   }
@@ -384,7 +392,6 @@
     return Arrays.toString(digest);
   }
 
-
   public static String times(String string, int count) {
     StringBuilder builder = new StringBuilder();
     while (--count >= 0) {