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.sdk.coders;
  
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.OutputStream;
  import org.apache.beam.sdk.util.common.ElementByteSizeObserver;
  import org.apache.beam.sdk.values.TypeDescriptor;
  import org.joda.time.Duration;
  import org.joda.time.ReadableDuration;
  
  /**
   * A {@link Coder} that encodes a joda {@link Duration} as a {@link Long} using the format of {@link
   * VarLongCoder}.
   */
  public class DurationCoder extends AtomicCoder<ReadableDuration> {
  
    public static DurationCoder of() {
      return INSTANCE;
    }
  
    /////////////////////////////////////////////////////////////////////////////
  
    private static final DurationCoder INSTANCE = new DurationCoder();
    private static final TypeDescriptor<ReadableDuration> TYPE_DESCRIPTOR =
        new TypeDescriptor<ReadableDuration>() {};
  
    private static final VarLongCoder LONG_CODER = VarLongCoder.of();
  
    private DurationCoder() {}
  
    private Long toLong(ReadableDuration value) {
      return value.getMillis();
    }
  
    private ReadableDuration fromLong(Long decoded) {
      return Duration.millis(decoded);
    }
  
    @Override
    public void encode(ReadableDuration value, OutputStream outStream)
        throws CoderException, IOException {
      if (value == null) {
        throw new CoderException("cannot encode a null ReadableDuration");
      }
      LONG_CODER.encode(toLong(value), outStream);
    }
  
    @Override
    public ReadableDuration decode(InputStream inStream) throws CoderException, IOException {
      return fromLong(LONG_CODER.decode(inStream));
    }
  
    @Override
    public void verifyDeterministic() {
      LONG_CODER.verifyDeterministic();
    }
  
    /**
     * {@inheritDoc}
     *
     * @return {@code true}. This coder is injective.
     */
    @Override
    public boolean consistentWithEquals() {
      return true;
    }
  
    /**
     * {@inheritDoc}
     *
     * @return {@code true}, because it is cheap to ascertain the byte size of a long.
     */
    @Override
    public boolean isRegisterByteSizeObserverCheap(ReadableDuration value) {
      return LONG_CODER.isRegisterByteSizeObserverCheap(toLong(value));
    }
  
    @Override
    public void registerByteSizeObserver(ReadableDuration value, ElementByteSizeObserver observer)
        throws Exception {
      LONG_CODER.registerByteSizeObserver(toLong(value), observer);
    }
  
    @Override
    public TypeDescriptor<ReadableDuration> getEncodedTypeDescriptor() {
      return TYPE_DESCRIPTOR;
    }
  }
  