org.apache.tez.mapreduce.lib.MRInputUtils.java Source code

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Here is the source code for org.apache.tez.mapreduce.lib.MRInputUtils.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.tez.mapreduce.lib;

import java.io.IOException;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.classification.InterfaceAudience.Private;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FSDataInputStream;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.io.serializer.Deserializer;
import org.apache.hadoop.io.serializer.SerializationFactory;
import org.apache.hadoop.mapred.InputSplit;
import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.mapreduce.split.JobSplit.TaskSplitIndex;
import org.apache.hadoop.mapreduce.split.JobSplit.TaskSplitMetaInfo;
import org.apache.hadoop.mapreduce.split.SplitMetaInfoReaderTez;
import org.apache.tez.common.counters.TezCounter;
import org.apache.tez.mapreduce.hadoop.MRInputHelpers;
import org.apache.tez.mapreduce.protos.MRRuntimeProtos.MRSplitProto;

/**
 * Helper methods for InputFormat based Inputs. Private to Tez.
 */
@Private
public class MRInputUtils {

    private static final Log LOG = LogFactory.getLog(MRInputUtils.class);

    public static TaskSplitMetaInfo[] readSplits(Configuration conf) throws IOException {
        TaskSplitMetaInfo[] allTaskSplitMetaInfo;
        allTaskSplitMetaInfo = SplitMetaInfoReaderTez.readSplitMetaInfo(conf, FileSystem.getLocal(conf));
        return allTaskSplitMetaInfo;
    }

    public static org.apache.hadoop.mapreduce.InputSplit getNewSplitDetailsFromEvent(MRSplitProto splitProto,
            Configuration conf) throws IOException {
        SerializationFactory serializationFactory = new SerializationFactory(conf);
        return MRInputHelpers.createNewFormatSplitFromUserPayload(splitProto, serializationFactory);
    }

    @SuppressWarnings("unchecked")
    public static org.apache.hadoop.mapreduce.InputSplit getNewSplitDetailsFromDisk(TaskSplitIndex splitMetaInfo,
            JobConf jobConf, TezCounter splitBytesCounter) throws IOException {
        Path file = new Path(splitMetaInfo.getSplitLocation());
        long offset = splitMetaInfo.getStartOffset();

        // Split information read from local filesystem.
        FileSystem fs = FileSystem.getLocal(jobConf);
        file = fs.makeQualified(file);
        LOG.info("Reading input split file from : " + file);
        FSDataInputStream inFile = fs.open(file);
        inFile.seek(offset);
        String className = Text.readString(inFile);
        Class<org.apache.hadoop.mapreduce.InputSplit> cls;
        try {
            cls = (Class<org.apache.hadoop.mapreduce.InputSplit>) jobConf.getClassByName(className);
        } catch (ClassNotFoundException ce) {
            IOException wrap = new IOException("Split class " + className + " not found");
            wrap.initCause(ce);
            throw wrap;
        }
        SerializationFactory factory = new SerializationFactory(jobConf);
        Deserializer<org.apache.hadoop.mapreduce.InputSplit> deserializer = (Deserializer<org.apache.hadoop.mapreduce.InputSplit>) factory
                .getDeserializer(cls);
        deserializer.open(inFile);
        org.apache.hadoop.mapreduce.InputSplit split = deserializer.deserialize(null);
        long pos = inFile.getPos();
        if (splitBytesCounter != null) {
            splitBytesCounter.increment(pos - offset);
        }
        inFile.close();
        return split;
    }

    @SuppressWarnings("unchecked")
    public static InputSplit getOldSplitDetailsFromDisk(TaskSplitIndex splitMetaInfo, JobConf jobConf,
            TezCounter splitBytesCounter) throws IOException {
        Path file = new Path(splitMetaInfo.getSplitLocation());
        FileSystem fs = FileSystem.getLocal(jobConf);
        file = fs.makeQualified(file);
        LOG.info("Reading input split file from : " + file);
        long offset = splitMetaInfo.getStartOffset();

        FSDataInputStream inFile = fs.open(file);
        inFile.seek(offset);
        String className = Text.readString(inFile);
        Class<org.apache.hadoop.mapred.InputSplit> cls;
        try {
            cls = (Class<org.apache.hadoop.mapred.InputSplit>) jobConf.getClassByName(className);
        } catch (ClassNotFoundException ce) {
            IOException wrap = new IOException("Split class " + className + " not found");
            wrap.initCause(ce);
            throw wrap;
        }
        SerializationFactory factory = new SerializationFactory(jobConf);
        Deserializer<org.apache.hadoop.mapred.InputSplit> deserializer = (Deserializer<org.apache.hadoop.mapred.InputSplit>) factory
                .getDeserializer(cls);
        deserializer.open(inFile);
        org.apache.hadoop.mapred.InputSplit split = deserializer.deserialize(null);
        long pos = inFile.getPos();
        if (splitBytesCounter != null) {
            splitBytesCounter.increment(pos - offset);
        }
        inFile.close();
        return split;
    }

    @Private
    public static InputSplit getOldSplitDetailsFromEvent(MRSplitProto splitProto, Configuration conf)
            throws IOException {
        SerializationFactory serializationFactory = new SerializationFactory(conf);
        return MRInputHelpers.createOldFormatSplitFromUserPayload(splitProto, serializationFactory);
    }
}