com.ema.hadoop.wordcount.WordCount_cache.java Source code

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Here is the source code for com.ema.hadoop.wordcount.WordCount_cache.java

Source

package com.ema.hadoop.wordcount;

/*
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import java.io.BufferedWriter;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import static java.lang.System.out;
import java.net.URI;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.IntWritable;
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.output.FileOutputFormat;
import org.apache.hadoop.util.Progressable;

/**
 *
 * @author sharispe
 */
public class WordCount_cache {

    public static void main(String[] args) throws Exception {

        if (args.length != 2) {
            System.err.println("Usage: WordCount <input path> <output path>");
            System.exit(-1);
        }

        // First we write the stop word list
        // it could also be a file manually loaded into HDFS

        String[] stopwords = { "the", "a" };
        Configuration configuration = new Configuration();
        FileSystem hdfs = FileSystem.get(new URI("hdfs://localhost:9000"), configuration);
        Path file = new Path("hdfs://localhost:9000/user/student/stop_words.txt");
        if (hdfs.exists(file)) {
            hdfs.delete(file, true);
        }
        OutputStream os = hdfs.create(file, new Progressable() {
            @Override
            public void progress() {
                out.println("...bytes written");
            }
        });
        BufferedWriter br = new BufferedWriter(new OutputStreamWriter(os, "UTF-8"));
        for (String w : stopwords) {
            br.write(w + "\n");
        }

        br.close();
        hdfs.close();

        Job job = Job.getInstance();
        job.addCacheFile(new Path("hdfs://localhost:9000/user/student/stop_words.txt").toUri());

        job.setJarByClass(WordCount_cache.class);
        job.setJobName("Word count job");

        FileInputFormat.setInputPaths(job, new Path(args[0]));
        FileOutputFormat.setOutputPath(job, new Path(args[1]));

        job.setMapperClass(WCMapper_cache.class);
        job.setReducerClass(WCReducer.class);

        job.setOutputKeyClass(Text.class);
        job.setOutputValueClass(IntWritable.class);

        System.exit(job.waitForCompletion(true) ? 0 : 1);
    }
}