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;
020
021import java.io.IOException;
022
023import org.apache.hadoop.classification.InterfaceAudience;
024import org.apache.hadoop.classification.InterfaceStability;
025import org.apache.hadoop.io.Closeable;
026
027/** 
028 * Base class for {@link Mapper} and {@link Reducer} implementations.
029 * 
030 * <p>Provides default no-op implementations for a few methods, most non-trivial
031 * applications need to override some of them.</p>
032 */
033@InterfaceAudience.Public
034@InterfaceStability.Stable
035public class MapReduceBase implements Closeable, JobConfigurable {
036
037  /** Default implementation that does nothing. */
038  public void close() throws IOException {
039  }
040
041  /** Default implementation that does nothing. */
042  public void configure(JobConf job) {
043  }
044
045}