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    
019    package org.apache.hadoop.mapreduce.lib.join;
020    
021    import java.io.IOException;
022    
023    import org.apache.hadoop.classification.InterfaceAudience;
024    import org.apache.hadoop.classification.InterfaceStability;
025    import org.apache.hadoop.io.Writable;
026    import org.apache.hadoop.io.WritableComparable;
027    import org.apache.hadoop.mapreduce.InputFormat;
028    import org.apache.hadoop.mapreduce.InputSplit;
029    import org.apache.hadoop.mapreduce.TaskAttemptContext;
030    
031    /**
032     * Refinement of InputFormat requiring implementors to provide
033     * ComposableRecordReader instead of RecordReader.
034     */
035    @InterfaceAudience.Public
036    @InterfaceStability.Stable
037    public abstract class ComposableInputFormat<K extends WritableComparable<?>,
038                                                V extends Writable>
039        extends InputFormat<K,V> {
040    
041      public abstract ComposableRecordReader<K,V> createRecordReader(
042        InputSplit split, TaskAttemptContext context) 
043        throws IOException, InterruptedException;
044    
045    }