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    package org.apache.hadoop.mapreduce.lib.output;
019    
020    import java.io.IOException;
021    
022    import org.apache.hadoop.classification.InterfaceAudience;
023    import org.apache.hadoop.classification.InterfaceStability;
024    import org.apache.hadoop.mapreduce.TaskAttemptContext;
025    
026    /**
027     * Interface for an {@link org.apache.hadoop.mapreduce.OutputCommitter}
028     * implementing partial commit of task output, as during preemption.
029     */
030    @InterfaceAudience.Public
031    @InterfaceStability.Evolving
032    public interface PartialOutputCommitter {
033    
034      /**
035       * Remove all previously committed outputs from prior executions of this task.
036       * @param context Context for cleaning up previously promoted output.
037       * @throws IOException If cleanup fails, then the state of the task my not be
038       *                     well defined.
039       */
040      public void cleanUpPartialOutputForTask(TaskAttemptContext context)
041        throws IOException;
042    
043    }