clustering.simhash.Driver.java Source code

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Here is the source code for clustering.simhash.Driver.java

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/*
 * 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 clustering.simhash;

import clustering.Utils.MapReduceUtils;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.conf.Configured;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Job;
import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;
import org.apache.hadoop.mapreduce.lib.input.KeyValueTextInputFormat;
import org.apache.hadoop.mapreduce.lib.jobcontrol.ControlledJob;
import org.apache.hadoop.mapreduce.lib.jobcontrol.JobControl;
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
import org.apache.hadoop.util.Tool;
import org.apache.hadoop.util.ToolRunner;

/**
 * WorkflowDriver class for pre-clustering data.
 * Step 1 calculate a SimHash signature for every item,
 * and group items with similar signatures together.
 * Step 2 take the first item from each group as a representative.
 *
 * @author edwardlol
 *         Created by edwardlol on 17-4-21.
 */
public class Driver extends Configured implements Tool {
    //~  Methods ---------------------------------------------------------------

    @Override
    public int run(String[] args) throws Exception {
        if (args.length < 2) {
            System.err.printf("usage: %s init_result_dir output_dir [simhash_threshold]\n",
                    getClass().getSimpleName());
            System.exit(1);
        }

        Path step1_outputDir = new Path(args[1] + "/step1");

        Configuration conf = getConf();
        conf = MapReduceUtils.initConf(conf);

        if (args.length > 2) {
            conf.setInt("simhash.threshold", Integer.valueOf(args[2]));
        } else {
            conf.setInt("simhash.threshold", 3);
        }

        JobControl jobControl = new JobControl("simhash jobs");

        Job job1 = Job.getInstance(conf, "simhash step1 job");
        job1.setJarByClass(Driver.class);

        FileInputFormat.addInputPath(job1, new Path(args[0]));
        job1.setInputFormatClass(KeyValueTextInputFormat.class);

        job1.setMapperClass(Step1Mapper.class);
        job1.setMapOutputKeyClass(LongWritable.class);
        job1.setMapOutputValueClass(Text.class);

        job1.setReducerClass(Step1Reducer.class);
        job1.setOutputKeyClass(IntWritable.class);
        job1.setOutputValueClass(Text.class);

        FileOutputFormat.setOutputPath(job1, step1_outputDir);

        ControlledJob controlledJob1 = new ControlledJob(conf);
        controlledJob1.setJob(job1);
        jobControl.addJob(controlledJob1);

        Job job2 = Job.getInstance(conf, "simhash step2 job");
        job2.setJarByClass(Driver.class);

        FileInputFormat.addInputPath(job2, step1_outputDir);
        job2.setInputFormatClass(KeyValueTextInputFormat.class);

        job2.setMapperClass(Step2Mapper.class);
        job2.setMapOutputKeyClass(IntWritable.class);
        job2.setMapOutputValueClass(Text.class);

        job2.setReducerClass(Step2Reducer.class);
        job2.setOutputKeyClass(IntWritable.class);
        job2.setOutputValueClass(Text.class);

        FileOutputFormat.setOutputPath(job2, new Path(args[1] + "/result"));

        ControlledJob controlledJob2 = new ControlledJob(conf);
        controlledJob2.setJob(job2);
        controlledJob2.addDependingJob(controlledJob1);
        jobControl.addJob(controlledJob2);

        long starttime = System.currentTimeMillis();
        clustering.Utils.MapReduceUtils.runJobs(jobControl);

        boolean complete = job2.waitForCompletion(true);
        long endtime = System.currentTimeMillis();
        System.out.println("simhash job finished in: " + (endtime - starttime) / 1000 + " seconds");

        return complete ? 0 : 1;
    }

    //~  Entrance --------------------------------------------------------------

    public static void main(String[] args) throws Exception {
        Configuration configuration = new Configuration();
        System.exit(ToolRunner.run(configuration, new Driver(), args));
    }

}

// End WorkflowDriver.java