edu.ub.ahstfg.indexer.wordcount.WordCount.java Source code

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Here is the source code for edu.ub.ahstfg.indexer.wordcount.WordCount.java

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/*
 * WordCount.java is part of HHCluster.
 *
 * HHCluster is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * HHCluster is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with HHCluster.  If not, see <http://www.gnu.org/licenses/>.
 */

package edu.ub.ahstfg.indexer.wordcount;

import java.net.URI;

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.LongWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapred.FileInputFormat;
import org.apache.hadoop.mapred.FileOutputFormat;
import org.apache.hadoop.mapred.JobClient;
import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.mapred.TextOutputFormat;
import org.apache.hadoop.mapred.lib.LongSumReducer;
import org.apache.hadoop.util.Tool;
import org.apache.hadoop.util.ToolRunner;
import org.apache.log4j.Logger;
import org.commoncrawl.hadoop.mapred.ArcInputFormat;

public class WordCount extends Configured implements Tool {

    private static final Logger LOG = Logger.getLogger(WordCount.class);

    private String inputPath;
    private String outputPath;

    public WordCount(String inputPath, String outputPath) {
        this.inputPath = inputPath;
        this.outputPath = outputPath;
    }

    @Override
    public int run(String[] args) throws Exception {

        LOG.info("Creating Hadoop job for ARC input files word count.");
        JobConf job = new JobConf(getConf());
        job.setJarByClass(WordCount.class);

        LOG.info("Setting input path to '" + inputPath + "'");
        FileInputFormat.setInputPaths(job, new Path(inputPath));
        // Set filters if it's necessary.

        LOG.info("Clearing the output path at '" + outputPath + "'");
        // Change URI to Path if it's necessary.
        FileSystem fs = FileSystem.get(new URI(outputPath), job);

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

        LOG.info("Setting output path to '" + outputPath + "'");
        FileOutputFormat.setOutputPath(job, new Path(outputPath));
        FileOutputFormat.setCompressOutput(job, false);

        LOG.info("Setting input format.");
        // job.setInputFormat(TextInputFormat.class);
        job.setInputFormat(ArcInputFormat.class);
        LOG.info("Setting output format.");
        job.setOutputFormat(TextOutputFormat.class);

        LOG.info("Setting output data types.");
        job.setOutputKeyClass(Text.class);
        job.setOutputValueClass(LongWritable.class);

        LOG.info("Setting mapper and reducer.");
        // job.setMapperClass(WordCountTextInputMapper.class);
        job.setMapperClass(WordCountArcInputMapper.class);
        job.setReducerClass(LongSumReducer.class);

        if (JobClient.runJob(job).isSuccessful()) {
            return 0;
        } else {
            return 1;
        }
    }

    public static void main(String[] args) {
        String inputPath = args[0];
        String outputPath = args[1];
        int res;
        try {
            res = ToolRunner.run(new Configuration(), new WordCount(inputPath, outputPath), args);
            System.exit(res);
        } catch (Exception e) {
            LOG.error(e.getMessage());
        }
    }

}