content: /*
   * Licensed to the Apache Software Foundation (ASF) under one
   * or more contributor license agreements.  See the NOTICE file
   * distributed with this work for additional information
   * regarding copyright ownership.  The ASF licenses this file
   * to you under the Apache License, Version 2.0 (the
   * "License"); you may not use this file except in compliance
   * with the License.  You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package org.apache.beam.runners.dataflow.worker;
  
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.OutputStream;
  import org.apache.beam.sdk.coders.AtomicCoder;
  import org.apache.beam.sdk.coders.Coder;
  import org.apache.beam.sdk.util.VarInt;
  import org.apache.beam.vendor.grpc.v1p69p0.com.google.protobuf.ByteString;
  import org.apache.beam.vendor.guava.v32_1_2_jre.com.google.common.io.ByteStreams;
  
  /**
   * A simplified {@link Coder} for {@link ByteString}, to avoid a dependency on
   * beam-java-sdk-extensions-protobuf.
   */
  public class ByteStringCoder extends AtomicCoder<ByteString> {
    public static ByteStringCoder of() {
      return INSTANCE;
    }
  
    private static final ByteStringCoder INSTANCE = new ByteStringCoder();
  
    private ByteStringCoder() {}
  
    @Override
    public void encode(ByteString value, OutputStream os) throws IOException {
      VarInt.encode(value.size(), os);
      value.writeTo(os);
    }
  
    @Override
    public ByteString decode(InputStream is) throws IOException {
      int size = VarInt.decodeInt(is);
      return ByteString.readFrom(ByteStreams.limit(is, size), size);
    }
  }
  