eu.stratosphere.myriad.driver.hadoop.MyriadDriverHadoopJob.java Source code

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Here is the source code for eu.stratosphere.myriad.driver.hadoop.MyriadDriverHadoopJob.java

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/***********************************************************************************************************************
 *
 * Copyright (C) 2010 by the Stratosphere project (http://stratosphere.eu)
 *
 * Licensed 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 eu.stratosphere.myriad.driver.hadoop;

import java.io.IOException;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.conf.Configured;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.NullWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapred.FileOutputFormat;
import org.apache.hadoop.mapred.JobClient;
import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.mapred.Mapper;
import org.apache.hadoop.mapred.OutputCollector;
import org.apache.hadoop.mapred.Reporter;
import org.apache.hadoop.mapred.TextOutputFormat;

import eu.stratosphere.myriad.driver.MyriadDriverJob;
import eu.stratosphere.myriad.driver.parameters.DriverJobParameters;

/**
 * @author Alexander Alexandrov (alexander.alexandrov@tu-berlin.de)
 */
@SuppressWarnings("deprecation")
public class MyriadDriverHadoopJob extends Configured implements MyriadDriverJob {

    private DriverJobParameters parameters;

    public MyriadDriverHadoopJob(DriverJobParameters parameters) {
        super(new Configuration());
        this.parameters = parameters;
    }

    @Override
    public void run() throws IOException {
        JobClient.runJob(this.createJobConf());
    }

    @Override
    public void removeOutputPath() throws IOException {
        FileSystem fs = FileSystem.get(getConf());
        Path outputPath = new Path(this.parameters.getJobOutputPath());

        if (fs.exists(outputPath)) {
            fs.delete(outputPath, true);
        }
    }

    private JobConf createJobConf() {
        // create job
        JobConf conf = new JobConf(getConf());

        conf.setJarByClass(MyriadDriverHadoopJob.class);
        conf.setJobName(String.format("%s", this.parameters.getDGenName()));

        conf.setOutputKeyClass(NullWritable.class);
        conf.setOutputValueClass(Text.class);

        conf.setMapperClass(IdentityMapper.class);
        conf.setNumReduceTasks(0);

        conf.setInputFormat(MyriadInputFormat.class);
        conf.setOutputFormat(TextOutputFormat.class);

        // input format configuration
        MyriadInputFormat.setDriverJobParameters(conf, this.parameters);
        // output format configuration
        FileOutputFormat.setOutputPath(conf, new Path(this.parameters.getJobOutputPath()));

        return conf;
    }

    public static class IdentityMapper implements Mapper<NullWritable, Text, NullWritable, Text> {

        @Override
        public void configure(JobConf job) {
        }

        @Override
        public void close() throws IOException {
        }

        @Override
        public void map(NullWritable k, Text v, OutputCollector<NullWritable, Text> o, Reporter r)
                throws IOException {
            o.collect(k, v);
        }
    }
}