org.apache.sysml.runtime.matrix.data.MultipleOutputCommitter.java Source code

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Here is the source code for org.apache.sysml.runtime.matrix.data.MultipleOutputCommitter.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.sysml.runtime.matrix.data;

import java.io.IOException;

import org.apache.hadoop.fs.FileStatus;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.mapred.FileOutputCommitter;
import org.apache.hadoop.mapred.FileOutputFormat;
import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.mapred.JobContext;
import org.apache.hadoop.mapred.TaskAttemptContext;
import org.apache.hadoop.mapred.TaskAttemptID;
import org.apache.sysml.runtime.matrix.mapred.MRJobConfiguration;

public class MultipleOutputCommitter extends FileOutputCommitter {
    // maintain the map of matrix index to its destination output dir
    // private HashMap<Byte, String> outputmap=new HashMap<Byte, String>();
    private String[] outputs;

    @Override
    public void setupJob(JobContext context) throws IOException {
        super.setupJob(context);
        // get output file directories and create directories
        JobConf conf = context.getJobConf();
        String[] loutputs = MRJobConfiguration.getOutputs(conf);
        for (String dir : loutputs) {
            Path path = new Path(dir);
            FileSystem fs = path.getFileSystem(conf);
            if (!fs.mkdirs(path))
                LOG.error("Mkdirs failed to create " + path.toString());
        }
    }

    @Override
    public void cleanupJob(JobContext context) throws IOException {
        JobConf conf = context.getJobConf();
        // do the clean up of temporary directory
        Path outputPath = FileOutputFormat.getOutputPath(conf);
        if (outputPath != null) {
            FileSystem fs = outputPath.getFileSystem(conf);
            context.getProgressible().progress();
            if (fs.exists(outputPath))
                fs.delete(outputPath, true);
        }
    }

    @Override
    public void commitTask(TaskAttemptContext context) throws IOException {
        JobConf conf = context.getJobConf();
        TaskAttemptID attemptId = context.getTaskAttemptID();

        // get the mapping between index to output filename
        outputs = MRJobConfiguration.getOutputs(conf);

        // get temp task output path (compatible with hadoop1 and hadoop2)
        Path taskOutPath = FileOutputFormat.getWorkOutputPath(conf);
        FileSystem fs = taskOutPath.getFileSystem(conf);
        if (!fs.exists(taskOutPath))
            throw new IOException("Task output path " + taskOutPath.toString() + "does not exist.");

        // move the task outputs to their final places
        context.getProgressible().progress();
        moveFinalTaskOutputs(context, fs, taskOutPath);

        // delete the temporary task-specific output directory
        if (!fs.delete(taskOutPath, true))
            LOG.debug(
                    "Failed to delete the temporary output directory of task: " + attemptId + " - " + taskOutPath);
    }

    private void moveFinalTaskOutputs(TaskAttemptContext context, FileSystem fs, Path taskOutput)
            throws IOException {
        context.getProgressible().progress();

        if (fs.getFileStatus(taskOutput).isDirectory()) {
            FileStatus[] files = fs.listStatus(taskOutput);
            if (files != null)
                for (FileStatus file : files) //for all files
                    if (!file.isDirectory()) //skip directories
                        moveFileToDestination(context, fs, file.getPath());
        }
    }

    private void moveFileToDestination(TaskAttemptContext context, FileSystem fs, Path file) throws IOException {
        TaskAttemptID attemptId = context.getTaskAttemptID();

        // get output index and final destination 
        String name = file.getName(); //e.g., 0-r-00000 
        int index = Integer.parseInt(name.substring(0, name.indexOf("-")));
        Path dest = new Path(outputs[index], name); //e.g., outX/0-r-00000

        // move file from 'file' to 'finalPath'
        if (!fs.rename(file, dest)) {
            if (!fs.delete(dest, true))
                throw new IOException("Failed to delete earlier output " + dest + " for rename of " + file
                        + " in task " + attemptId);
            if (!fs.rename(file, dest))
                throw new IOException(
                        "Failed to save output " + dest + " for rename of " + file + " in task: " + attemptId);
        }
    }
}