src/test/examples/simpleproto1/Simpleproto.java

// 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 simpleproto1;

import com.google.protobuf.UninitializedMessageException;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.Arrays;
import simpleproto1.GeneratedSimpleProto.Simple;

public class Simpleproto {

  private static final byte[] WITH_REQUIRED_FIELDS = new byte[]{7, 8, 42, 21, 0, 0, -10, 66};
  private static final byte[] WITH_MISSING_FIELD = new byte[]{2, 8, 42};


  public static void main(String... args) throws IOException {
    readProtoWithAllReqFields();
    partialBuildFails();
    partialReadFails();
  }

  private static void partialBuildFails() {
    Simple.Builder builder = Simple.newBuilder();
    builder.setId(32);
    try {
      builder.build();
    } catch (UninitializedMessageException e) {
      System.out.println("got exception");
    }
  }

  private static void partialReadFails() throws IOException {
    ByteArrayInputStream input = new ByteArrayInputStream(WITH_MISSING_FIELD);
    Simple.Builder builder = Simple.newBuilder();
    builder.mergeDelimitedFrom(input);
    try {
      builder.build();
    } catch (UninitializedMessageException e) {
      System.out.println("got exception");
    }
  }

  private static void readProtoWithAllReqFields() throws IOException {
    ByteArrayInputStream input = new ByteArrayInputStream(WITH_REQUIRED_FIELDS);
    Simple.Builder builder = Simple.newBuilder();
    builder.mergeDelimitedFrom(input);
    Simple simple = builder.build();
    ByteArrayOutputStream output = new ByteArrayOutputStream(WITH_REQUIRED_FIELDS.length);
    simple.writeDelimitedTo(output);
    System.out.println(Arrays.toString(output.toByteArray()));
    System.out.println(Arrays.equals(WITH_REQUIRED_FIELDS, output.toByteArray()));
  }
}