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.apex.malhar.flume.storage;
  
  import java.io.ByteArrayInputStream;
  import java.io.ByteArrayOutputStream;
  import java.util.HashMap;
  import java.util.Map;
  
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import org.apache.flume.Event;
  import org.apache.flume.event.EventBuilder;
  
  import com.esotericsoftware.kryo.Kryo;
  import com.esotericsoftware.kryo.io.Input;
  import com.esotericsoftware.kryo.io.Output;
  
  import com.datatorrent.api.StreamCodec;
  import com.datatorrent.netlet.util.Slice;
  
  /**
   * <p>EventCodec class.</p>
   *
   * @since 0.9.4
   */
  public class EventCodec implements StreamCodec<Event>
  {
    private final transient Kryo kryo;
  
    public EventCodec()
    {
      this.kryo = new Kryo();
      this.kryo.setClassLoader(Thread.currentThread().getContextClassLoader());
    }
  
    @Override
    public Object fromByteArray(Slice fragment)
    {
      ByteArrayInputStream is = new ByteArrayInputStream(fragment.buffer, fragment.offset, fragment.length);
      Input input = new Input(is);
  
      @SuppressWarnings("unchecked")
      HashMap<String, String> headers = kryo.readObjectOrNull(input, HashMap.class);
      byte[] body = kryo.readObjectOrNull(input, byte[].class);
      return EventBuilder.withBody(body, headers);
    }
  
    @Override
    public Slice toByteArray(Event event)
    {
      ByteArrayOutputStream os = new ByteArrayOutputStream();
      Output output = new Output(os);
  
      Map<String, String> headers = event.getHeaders();
      if (headers != null && headers.getClass() != HashMap.class) {
        HashMap<String, String> tmp = new HashMap<String, String>(headers.size());
        tmp.putAll(headers);
        headers = tmp;
      }
      kryo.writeObjectOrNull(output, headers, HashMap.class);
      kryo.writeObjectOrNull(output, event.getBody(), byte[].class);
      output.flush();
      final byte[] bytes = os.toByteArray();
      return new Slice(bytes, 0, bytes.length);
    }
  
    @Override
    public int getPartition(Event o)
    {
      return o.hashCode();
    }
  
    private static final Logger logger = LoggerFactory.getLogger(EventCodec.class);
  }
  