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 */
018
019package org.apache.hadoop.mapred.lib;
020
021import org.apache.hadoop.classification.InterfaceAudience;
022import org.apache.hadoop.classification.InterfaceStability;
023import org.apache.hadoop.fs.FileSystem;
024import org.apache.hadoop.mapred.JobConf;
025import org.apache.hadoop.mapred.OutputFormat;
026import org.apache.hadoop.mapred.RecordWriter;
027import org.apache.hadoop.mapred.Reporter;
028import org.apache.hadoop.util.Progressable;
029
030/**
031 * Consume all outputs and put them in /dev/null. 
032 */
033@InterfaceAudience.Public
034@InterfaceStability.Stable
035public class NullOutputFormat<K, V> implements OutputFormat<K, V> {
036  
037  public RecordWriter<K, V> getRecordWriter(FileSystem ignored, JobConf job, 
038                                      String name, Progressable progress) {
039    return new RecordWriter<K, V>(){
040        public void write(K key, V value) { }
041        public void close(Reporter reporter) { }
042      };
043  }
044  
045  public void checkOutputSpecs(FileSystem ignored, JobConf job) { }
046}