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1   /**
2    *
3    * Licensed to the Apache Software Foundation (ASF) under one
4    * or more contributor license agreements.  See the NOTICE file
5    * distributed with this work for additional information
6    * regarding copyright ownership.  The ASF licenses this file
7    * to you under the Apache License, Version 2.0 (the
8    * "License"); you may not use this file except in compliance
9    * with the License.  You may obtain a copy of the License at
10   *
11   *     http://www.apache.org/licenses/LICENSE-2.0
12   *
13   * Unless required by applicable law or agreed to in writing, software
14   * distributed under the License is distributed on an "AS IS" BASIS,
15   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16   * See the License for the specific language governing permissions and
17   * limitations under the License.
18   */
19  package org.apache.hadoop.hbase.mapred;
20  
21  import java.io.IOException;
22  import java.util.Iterator;
23  
24  import org.apache.commons.logging.Log;
25  import org.apache.commons.logging.LogFactory;
26  import org.apache.hadoop.classification.InterfaceAudience;
27  import org.apache.hadoop.classification.InterfaceStability;
28  import org.apache.hadoop.hbase.client.Put;
29  import org.apache.hadoop.hbase.io.ImmutableBytesWritable;
30  import org.apache.hadoop.mapred.MapReduceBase;
31  import org.apache.hadoop.mapred.OutputCollector;
32  import org.apache.hadoop.mapred.Reporter;
33  
34  /**
35   * Write to table each key, record pair
36   */
37  @Deprecated
38  @InterfaceAudience.Public
39  @InterfaceStability.Stable
40  public class IdentityTableReduce
41  extends MapReduceBase
42  implements TableReduce<ImmutableBytesWritable, Put> {
43    @SuppressWarnings("unused")
44    private static final Log LOG =
45      LogFactory.getLog(IdentityTableReduce.class.getName());
46  
47    /**
48     * No aggregation, output pairs of (key, record)
49     * @param key
50     * @param values
51     * @param output
52     * @param reporter
53     * @throws IOException
54     */
55    public void reduce(ImmutableBytesWritable key, Iterator<Put> values,
56        OutputCollector<ImmutableBytesWritable, Put> output,
57        Reporter reporter)
58        throws IOException {
59  
60      while(values.hasNext()) {
61        output.collect(key, values.next());
62      }
63    }
64  }