001/**
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *     http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018package org.apache.hadoop.hbase.mapreduce;
019
020import java.io.DataInputStream;
021import java.io.DataOutputStream;
022import java.io.IOException;
023import java.io.InputStream;
024import java.io.OutputStream;
025
026import org.apache.hadoop.hbase.Cell;
027import org.apache.hadoop.hbase.PrivateCellUtil;
028import org.apache.hadoop.hbase.KeyValue;
029import org.apache.hadoop.hbase.KeyValueUtil;
030import org.apache.hadoop.hbase.util.Bytes;
031import org.apache.yetus.audience.InterfaceAudience;
032import org.apache.hadoop.io.serializer.Deserializer;
033import org.apache.hadoop.io.serializer.Serialization;
034import org.apache.hadoop.io.serializer.Serializer;
035
036/**
037 * Use to specify the type of serialization for the mappers and reducers
038 */
039@InterfaceAudience.Public
040public class CellSerialization implements Serialization<Cell> {
041  @Override
042  public boolean accept(Class<?> c) {
043    return Cell.class.isAssignableFrom(c);
044  }
045
046  @Override
047  public CellDeserializer getDeserializer(Class<Cell> t) {
048    return new CellDeserializer();
049  }
050
051  @Override
052  public CellSerializer getSerializer(Class<Cell> c) {
053    return new CellSerializer();
054  }
055
056  public static class CellDeserializer implements Deserializer<Cell> {
057    private DataInputStream dis;
058
059    @Override
060    public void close() throws IOException {
061      this.dis.close();
062    }
063
064    @Override
065    public KeyValue deserialize(Cell ignore) throws IOException {
066      // I can't overwrite the passed in KV, not from a proto kv, not just yet.  TODO
067      return KeyValueUtil.create(this.dis);
068    }
069
070    @Override
071    public void open(InputStream is) throws IOException {
072      this.dis = new DataInputStream(is);
073    }
074  }
075
076  public static class CellSerializer implements Serializer<Cell> {
077    private DataOutputStream dos;
078
079    @Override
080    public void close() throws IOException {
081      this.dos.close();
082    }
083
084    @Override
085    public void open(OutputStream os) throws IOException {
086      this.dos = new DataOutputStream(os);
087    }
088
089    @Override
090    public void serialize(Cell kv) throws IOException {
091      dos.writeInt(PrivateCellUtil.estimatedSerializedSizeOf(kv) - Bytes.SIZEOF_INT);
092      PrivateCellUtil.writeCell(kv, dos, true);
093    }
094  }
095}