org.apache.ignite.internal.processors.hadoop.v1.HadoopV1MapTask.java Source code

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Here is the source code for org.apache.ignite.internal.processors.hadoop.v1.HadoopV1MapTask.java

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/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.ignite.internal.processors.hadoop.v1;

import org.apache.hadoop.fs.*;
import org.apache.hadoop.mapred.*;
import org.apache.hadoop.util.*;
import org.apache.ignite.*;
import org.apache.ignite.internal.processors.hadoop.*;
import org.apache.ignite.internal.processors.hadoop.v2.*;

/**
 * Hadoop map task implementation for v1 API.
 */
public class HadoopV1MapTask extends HadoopV1Task {
    /** */
    private static final String[] EMPTY_HOSTS = new String[0];

    /**
     * Constructor.
     *
     * @param taskInfo 
     */
    public HadoopV1MapTask(HadoopTaskInfo taskInfo) {
        super(taskInfo);
    }

    /** {@inheritDoc} */
    @SuppressWarnings("unchecked")
    @Override
    public void run(HadoopTaskContext taskCtx) throws IgniteCheckedException {
        HadoopJob job = taskCtx.job();

        HadoopV2TaskContext ctx = (HadoopV2TaskContext) taskCtx;

        JobConf jobConf = ctx.jobConf();

        InputFormat inFormat = jobConf.getInputFormat();

        HadoopInputSplit split = info().inputSplit();

        InputSplit nativeSplit;

        if (split instanceof HadoopFileBlock) {
            HadoopFileBlock block = (HadoopFileBlock) split;

            nativeSplit = new FileSplit(new Path(block.file().toString()), block.start(), block.length(),
                    EMPTY_HOSTS);
        } else
            nativeSplit = (InputSplit) ctx.getNativeSplit(split);

        assert nativeSplit != null;

        Reporter reporter = new HadoopV1Reporter(taskCtx);

        HadoopV1OutputCollector collector = null;

        try {
            collector = collector(jobConf, ctx, !job.info().hasCombiner() && !job.info().hasReducer(), fileName(),
                    ctx.attemptId());

            RecordReader reader = inFormat.getRecordReader(nativeSplit, jobConf, reporter);

            Mapper mapper = ReflectionUtils.newInstance(jobConf.getMapperClass(), jobConf);

            Object key = reader.createKey();
            Object val = reader.createValue();

            assert mapper != null;

            try {
                try {
                    while (reader.next(key, val)) {
                        if (isCancelled())
                            throw new HadoopTaskCancelledException("Map task cancelled.");

                        mapper.map(key, val, collector, reporter);
                    }
                } finally {
                    mapper.close();
                }
            } finally {
                collector.closeWriter();
            }

            collector.commit();
        } catch (Exception e) {
            if (collector != null)
                collector.abort();

            throw new IgniteCheckedException(e);
        }
    }
}