src/main/java/com/android/tools/r8/graph/DexString.java - r8 - Git at Google

 // 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.graph;

 import com.android.tools.r8.dex.Constants;
 import com.android.tools.r8.dex.IndexedItemCollection;
 import com.android.tools.r8.naming.NamingLens;
 import com.android.tools.r8.utils.IdentifierUtils;
 import com.android.tools.r8.utils.StringUtils;
 import java.io.UTFDataFormatException;
 import java.util.Arrays;

 public class DexString extends IndexedDexItem implements PresortedComparable<DexString> {

   public static final DexString[] EMPTY_ARRAY = new DexString[]{};

   public final int size;  // size of this string, in UTF-16
   public final byte[] content;

   DexString(int size, byte[] content) {
     this.size = size;
     this.content = content;
   }

   public DexString(String string) {
     this.size = string.length();
     this.content = encodeToMutf8(string);
   }

   @Override
   public int computeHashCode() {
     return size * 7 + Arrays.hashCode(content);
   }

   @Override
   public boolean computeEquals(Object other) {
     if (other instanceof DexString) {
       DexString o = (DexString) other;
       return size == o.size && Arrays.equals(content, o.content);
     }
     return false;
   }

   @Override
   public String toString() {
     try {
       return decode();
     } catch (UTFDataFormatException e) {
       throw new RuntimeException("Bad format", e);
     }
   }

   public String toASCIIString() {
     try {
       return StringUtils.toASCIIString(decode());
     } catch (UTFDataFormatException e) {
       throw new RuntimeException("Bad format", e);
     }
   }

   public int numberOfLeadingSquareBrackets() {
     int result = 0;
     while (content.length > result && content[result] == ((byte) '[')) {
       result++;
     }
     return result;
   }

   // Inspired from /dex/src/main/java/com/android/dex/Mutf8.java
   private String decode() throws UTFDataFormatException {
     int s = 0;
     int p = 0;
     char[] out = new char[size];
     while (true) {
       char a = (char) (content[p++] & 0xff);
       if (a == 0) {
         return new String(out, 0, s);
       }
       out[s] = a;
       if (a < '\u0080') {
         s++;
       } else if ((a & 0xe0) == 0xc0) {
         int b = content[p++] & 0xff;
         if ((b & 0xC0) != 0x80) {
           throw new UTFDataFormatException("bad second byte");
         }
         out[s++] = (char) (((a & 0x1F) << 6) | (b & 0x3F));
       } else if ((a & 0xf0) == 0xe0) {
         int b = content[p++] & 0xff;
         int c = content[p++] & 0xff;
         if (((b & 0xC0) != 0x80) || ((c & 0xC0) != 0x80)) {
           throw new UTFDataFormatException("bad second or third byte");
         }
         out[s++] = (char) (((a & 0x0F) << 12) | ((b & 0x3F) << 6) | (c & 0x3F));
       } else {
         throw new UTFDataFormatException("bad byte");
       }
     }
   }

   // Inspired from /dex/src/main/java/com/android/dex/Mutf8.java
   private static int countBytes(String string) {
     int result = 0;
     for (int i = 0; i < string.length(); ++i) {
       char ch = string.charAt(i);
       if (ch != 0 && ch <= 127) { // U+0000 uses two bytes.
         ++result;
       } else if (ch <= 2047) {
         result += 2;
       } else {
         result += 3;
       }
       assert result > 0;
     }
     // We need an extra byte for the terminating '0'.
     return result + 1;
   }

   // Inspired from /dex/src/main/java/com/android/dex/Mutf8.java
   public static byte[] encodeToMutf8(String string) {
     byte[] result = new byte[countBytes(string)];
     int offset = 0;
     for (int i = 0; i < string.length(); i++) {
       char ch = string.charAt(i);
       if (ch != 0 && ch <= 127) { // U+0000 uses two bytes.
         result[offset++] = (byte) ch;
       } else if (ch <= 2047) {
         result[offset++] = (byte) (0xc0 | (0x1f & (ch >> 6)));
         result[offset++] = (byte) (0x80 | (0x3f & ch));
       } else {
         result[offset++] = (byte) (0xe0 | (0x0f & (ch >> 12)));
         result[offset++] = (byte) (0x80 | (0x3f & (ch >> 6)));
         result[offset++] = (byte) (0x80 | (0x3f & ch));
       }
     }
     result[offset] = 0;
     return result;
   }

   @Override
   public void collectIndexedItems(IndexedItemCollection indexedItems,
       DexMethod method, int instructionOffset) {
     indexedItems.addString(this);
   }

   @Override
   public int getOffset(ObjectToOffsetMapping mapping) {
     return mapping.getOffsetFor(this);
   }

   @Override
   public int compareTo(DexString other) {
     return sortedCompareTo(other.getSortedIndex());
   }

   @Override
   public int slowCompareTo(DexString other) {
     // Compare the bytes, as comparing UTF-8 encoded strings as strings of unsigned bytes gives
     // the same result as comparing the corresponding Unicode strings lexicographically by
     // codepoint. The only complication is the MUTF-8 encoding have the two byte encoding c0 80 of
     // the null character (U+0000) to allow embedded null characters.
     // Supplementary characters (unicode code points above U+FFFF) are always represented as
     // surrogate pairs and are compared using UTF-16 code units as per Java string semantics.
     int index = 0;
     while (true) {
       char b1 = (char) (content[index] & 0xff);
       char b2 = (char) (other.content[index] & 0xff);
       int diff = b1 - b2;
       if (diff != 0) {
         // Check if either string ends here.
         if (b1 == 0 || b2 == 0) {
           return diff;
         }
         // If either of the strings have the null character starting here, the null character
         // sort lowest.
         if ((b1 == 0xc0 && (content[index + 1] & 0xff) == 0x80) ||
             (b2 == 0xc0 && (other.content[index + 1] & 0xff) == 0x80)) {
           return b1 == 0xc0 && (content[index + 1] & 0xff) == 0x80 ? -1 : 1;
         }
         return diff;
       } else if (b1 == 0) {
         // Reached the end in both strings.
         return 0;
       }
       index++;
     }
   }

   @Override
   public int slowCompareTo(DexString other, NamingLens lens) {
     // The naming lens cannot affect strings.
     return slowCompareTo(other);
   }

   @Override
   public int layeredCompareTo(DexString other, NamingLens lens) {
     // Strings have no subparts that are already sorted.
     return slowCompareTo(other);
   }

   private static boolean isValidClassDescriptor(String string) {
     if (string.length() < 3
         || string.charAt(0) != 'L'
         || string.charAt(string.length() - 1) != ';') {
       return false;
     }
     if (string.charAt(1) == '/' || string.charAt(string.length() - 2) == '/') {
       return false;
     }
     int cp;
     for (int i = 1; i < string.length() - 1; i += Character.charCount(cp)) {
       cp = string.codePointAt(i);
       if (cp != '/' && !IdentifierUtils.isDexIdentifierPart(cp)) {
         return false;
       }
     }
     return true;
   }

   private static boolean isValidMethodName(String string) {
     if (string.isEmpty()) {
       return false;
     }
     // According to https://source.android.com/devices/tech/dalvik/dex-format#membername
     // '<' SimpleName '>' should be valid. However, the art verifier only allows <init>
     // and <clinit> which is reasonable.
     if ((string.charAt(0) == '<') &&
         (string.equals(Constants.INSTANCE_INITIALIZER_NAME) ||
             string.equals(Constants.CLASS_INITIALIZER_NAME))) {
       return true;
     }
     int cp;
     for (int i = 0; i < string.length(); i += Character.charCount(cp)) {
       cp = string.codePointAt(i);
       if (!IdentifierUtils.isDexIdentifierPart(cp)) {
         return false;
       }
     }
     return true;
   }

   private static boolean isValidFieldName(String string) {
     if (string.isEmpty()) {
       return false;
     }
     int start = 0;
     int end = string.length();
     if (string.charAt(0) == '<') {
       if (string.charAt(end - 1) == '>') {
         start = 1;
         --end;
       } else {
         return false;
       }
     }
     int cp;
     for (int i = start; i < end; i += Character.charCount(cp)) {
       cp = string.codePointAt(i);
       if (!IdentifierUtils.isDexIdentifierPart(cp)) {
         return false;
       }
     }
     return true;
   }

   public boolean isValidMethodName() {
     try {
       return isValidMethodName(decode());
     } catch (UTFDataFormatException e) {
       return false;
     }
   }

   public boolean isValidFieldName() {
     try {
       return isValidFieldName(decode());
     } catch (UTFDataFormatException e) {
       return false;
     }
   }

   public boolean isValidClassDescriptor() {
     try {
       return isValidClassDescriptor(decode());
     } catch (UTFDataFormatException e) {
       return false;
     }
   }

   public String dump() {
     StringBuilder builder = new StringBuilder();
     builder.append(toString());
     builder.append(" [");
     for (int i = 0; i < content.length; i++) {
       if (i > 0) {
         builder.append(" ");
       }
       builder.append(Integer.toHexString(content[i] & 0xff));
     }
     builder.append("]");
     return builder.toString();
   }

   public boolean startsWith(DexString prefix) {
     if (content.length < prefix.content.length) {
       return false;
     }
     for (int i = 0; i < prefix.content.length - 1; i++) {
       if (content[i] != prefix.content[i]) {
         return false;
       }
     }
     return true;
   }

   public boolean endsWith(DexString suffix) {
     if (content.length < suffix.content.length) {
       return false;
     }
     for (int i = content.length - suffix.content.length, j = 0; i < content.length; i++, j++) {
       if (content[i] != suffix.content[j]) {
         return false;
       }
     }
     return true;
   }
 }
	// 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.graph;

	import com.android.tools.r8.dex.Constants;
	import com.android.tools.r8.dex.IndexedItemCollection;
	import com.android.tools.r8.naming.NamingLens;
	import com.android.tools.r8.utils.IdentifierUtils;
	import com.android.tools.r8.utils.StringUtils;
	import java.io.UTFDataFormatException;
	import java.util.Arrays;

	public class DexString extends IndexedDexItem implements PresortedComparable<DexString> {

	public static final DexString[] EMPTY_ARRAY = new DexString[]{};

	public final int size; // size of this string, in UTF-16
	public final byte[] content;

	DexString(int size, byte[] content) {
	this.size = size;
	this.content = content;
	}

	public DexString(String string) {
	this.size = string.length();
	this.content = encodeToMutf8(string);
	}

	@Override
	public int computeHashCode() {
	return size * 7 + Arrays.hashCode(content);
	}

	@Override
	public boolean computeEquals(Object other) {
	if (other instanceof DexString) {
	DexString o = (DexString) other;
	return size == o.size && Arrays.equals(content, o.content);
	}
	return false;
	}

	@Override
	public String toString() {
	try {
	return decode();
	} catch (UTFDataFormatException e) {
	throw new RuntimeException("Bad format", e);
	}
	}

	public String toASCIIString() {
	try {
	return StringUtils.toASCIIString(decode());
	} catch (UTFDataFormatException e) {
	throw new RuntimeException("Bad format", e);
	}
	}

	public int numberOfLeadingSquareBrackets() {
	int result = 0;
	while (content.length > result && content[result] == ((byte) '[')) {
	result++;
	}
	return result;
	}

	// Inspired from /dex/src/main/java/com/android/dex/Mutf8.java
	private String decode() throws UTFDataFormatException {
	int s = 0;
	int p = 0;
	char[] out = new char[size];
	while (true) {
	char a = (char) (content[p++] & 0xff);
	if (a == 0) {
	return new String(out, 0, s);
	}
	out[s] = a;
	if (a < '\u0080') {
	s++;
	} else if ((a & 0xe0) == 0xc0) {
	int b = content[p++] & 0xff;
	if ((b & 0xC0) != 0x80) {
	throw new UTFDataFormatException("bad second byte");
	}
	out[s++] = (char) (((a & 0x1F) << 6) \| (b & 0x3F));
	} else if ((a & 0xf0) == 0xe0) {
	int b = content[p++] & 0xff;
	int c = content[p++] & 0xff;
	if (((b & 0xC0) != 0x80) \|\| ((c & 0xC0) != 0x80)) {
	throw new UTFDataFormatException("bad second or third byte");
	}
	out[s++] = (char) (((a & 0x0F) << 12) \| ((b & 0x3F) << 6) \| (c & 0x3F));
	} else {
	throw new UTFDataFormatException("bad byte");
	}
	}
	}

	// Inspired from /dex/src/main/java/com/android/dex/Mutf8.java
	private static int countBytes(String string) {
	int result = 0;
	for (int i = 0; i < string.length(); ++i) {
	char ch = string.charAt(i);
	if (ch != 0 && ch <= 127) { // U+0000 uses two bytes.
	++result;
	} else if (ch <= 2047) {
	result += 2;
	} else {
	result += 3;
	}
	assert result > 0;
	}
	// We need an extra byte for the terminating '0'.
	return result + 1;
	}

	// Inspired from /dex/src/main/java/com/android/dex/Mutf8.java
	public static byte[] encodeToMutf8(String string) {
	byte[] result = new byte[countBytes(string)];
	int offset = 0;
	for (int i = 0; i < string.length(); i++) {
	char ch = string.charAt(i);
	if (ch != 0 && ch <= 127) { // U+0000 uses two bytes.
	result[offset++] = (byte) ch;
	} else if (ch <= 2047) {
	result[offset++] = (byte) (0xc0 \| (0x1f & (ch >> 6)));
	result[offset++] = (byte) (0x80 \| (0x3f & ch));
	} else {
	result[offset++] = (byte) (0xe0 \| (0x0f & (ch >> 12)));
	result[offset++] = (byte) (0x80 \| (0x3f & (ch >> 6)));
	result[offset++] = (byte) (0x80 \| (0x3f & ch));
	}
	}
	result[offset] = 0;
	return result;
	}

	@Override
	public void collectIndexedItems(IndexedItemCollection indexedItems,
	DexMethod method, int instructionOffset) {
	indexedItems.addString(this);
	}

	@Override
	public int getOffset(ObjectToOffsetMapping mapping) {
	return mapping.getOffsetFor(this);
	}

	@Override
	public int compareTo(DexString other) {
	return sortedCompareTo(other.getSortedIndex());
	}

	@Override
	public int slowCompareTo(DexString other) {
	// Compare the bytes, as comparing UTF-8 encoded strings as strings of unsigned bytes gives
	// the same result as comparing the corresponding Unicode strings lexicographically by
	// codepoint. The only complication is the MUTF-8 encoding have the two byte encoding c0 80 of
	// the null character (U+0000) to allow embedded null characters.
	// Supplementary characters (unicode code points above U+FFFF) are always represented as
	// surrogate pairs and are compared using UTF-16 code units as per Java string semantics.
	int index = 0;
	while (true) {
	char b1 = (char) (content[index] & 0xff);
	char b2 = (char) (other.content[index] & 0xff);
	int diff = b1 - b2;
	if (diff != 0) {
	// Check if either string ends here.
	if (b1 == 0 \|\| b2 == 0) {
	return diff;
	}
	// If either of the strings have the null character starting here, the null character
	// sort lowest.
	if ((b1 == 0xc0 && (content[index + 1] & 0xff) == 0x80) \|\|
	(b2 == 0xc0 && (other.content[index + 1] & 0xff) == 0x80)) {
	return b1 == 0xc0 && (content[index + 1] & 0xff) == 0x80 ? -1 : 1;
	}
	return diff;
	} else if (b1 == 0) {
	// Reached the end in both strings.
	return 0;
	}
	index++;
	}
	}

	@Override
	public int slowCompareTo(DexString other, NamingLens lens) {
	// The naming lens cannot affect strings.
	return slowCompareTo(other);
	}

	@Override
	public int layeredCompareTo(DexString other, NamingLens lens) {
	// Strings have no subparts that are already sorted.
	return slowCompareTo(other);
	}

	private static boolean isValidClassDescriptor(String string) {
	if (string.length() < 3
	\|\| string.charAt(0) != 'L'
	\|\| string.charAt(string.length() - 1) != ';') {
	return false;
	}
	if (string.charAt(1) == '/' \|\| string.charAt(string.length() - 2) == '/') {
	return false;
	}
	int cp;
	for (int i = 1; i < string.length() - 1; i += Character.charCount(cp)) {
	cp = string.codePointAt(i);
	if (cp != '/' && !IdentifierUtils.isDexIdentifierPart(cp)) {
	return false;
	}
	}
	return true;
	}

	private static boolean isValidMethodName(String string) {
	if (string.isEmpty()) {
	return false;
	}
	// According to https://source.android.com/devices/tech/dalvik/dex-format#membername
	// '<' SimpleName '>' should be valid. However, the art verifier only allows <init>
	// and <clinit> which is reasonable.
	if ((string.charAt(0) == '<') &&
	(string.equals(Constants.INSTANCE_INITIALIZER_NAME) \|\|
	string.equals(Constants.CLASS_INITIALIZER_NAME))) {
	return true;
	}
	int cp;
	for (int i = 0; i < string.length(); i += Character.charCount(cp)) {
	cp = string.codePointAt(i);
	if (!IdentifierUtils.isDexIdentifierPart(cp)) {
	return false;
	}
	}
	return true;
	}

	private static boolean isValidFieldName(String string) {
	if (string.isEmpty()) {
	return false;
	}
	int start = 0;
	int end = string.length();
	if (string.charAt(0) == '<') {
	if (string.charAt(end - 1) == '>') {
	start = 1;
	--end;
	} else {
	return false;
	}
	}
	int cp;
	for (int i = start; i < end; i += Character.charCount(cp)) {
	cp = string.codePointAt(i);
	if (!IdentifierUtils.isDexIdentifierPart(cp)) {
	return false;
	}
	}
	return true;
	}

	public boolean isValidMethodName() {
	try {
	return isValidMethodName(decode());
	} catch (UTFDataFormatException e) {
	return false;
	}
	}

	public boolean isValidFieldName() {
	try {
	return isValidFieldName(decode());
	} catch (UTFDataFormatException e) {
	return false;
	}
	}

	public boolean isValidClassDescriptor() {
	try {
	return isValidClassDescriptor(decode());
	} catch (UTFDataFormatException e) {
	return false;
	}
	}

	public String dump() {
	StringBuilder builder = new StringBuilder();
	builder.append(toString());
	builder.append(" [");
	for (int i = 0; i < content.length; i++) {
	if (i > 0) {
	builder.append(" ");
	}
	builder.append(Integer.toHexString(content[i] & 0xff));
	}
	builder.append("]");
	return builder.toString();
	}

	public boolean startsWith(DexString prefix) {
	if (content.length < prefix.content.length) {
	return false;
	}
	for (int i = 0; i < prefix.content.length - 1; i++) {
	if (content[i] != prefix.content[i]) {
	return false;
	}
	}
	return true;
	}

	public boolean endsWith(DexString suffix) {
	if (content.length < suffix.content.length) {
	return false;
	}
	for (int i = content.length - suffix.content.length, j = 0; i < content.length; i++, j++) {
	if (content[i] != suffix.content[j]) {
	return false;
	}
	}
	return true;
	}
	}