adts.PrepareInput.java Source code

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Here is the source code for adts.PrepareInput.java

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/**************************************************
Copyright (C) 2014  Raptis Dimos <raptis.dimos@yahoo.gr>
    
    
This program 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.
    
This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
**************************************************/

package adts;

import java.io.IOException;
import java.util.*;
import java.security.*;

import org.apache.hadoop.fs.Path;
import org.apache.hadoop.conf.*;
import org.apache.hadoop.io.*;
import org.apache.hadoop.mapreduce.*;
import org.apache.hadoop.mapreduce.Mapper.Context;
import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;
import org.apache.hadoop.mapreduce.lib.input.TextInputFormat;
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
import org.apache.hadoop.mapreduce.lib.output.TextOutputFormat;

import adts.SuccessfullQueries.Map;
import adts.SuccessfullQueries.Reduce;

public class PrepareInput {

    public static class Map extends Mapper<LongWritable, Text, Text, Text> {
        MessageDigest md;

        public void map(LongWritable key, Text value, Context context) throws IOException, InterruptedException {
            String line = value.toString();
            try {
                md = MessageDigest.getInstance("MD5");
            } catch (NoSuchAlgorithmException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            md.update(line.getBytes());
            byte[] thedigest = md.digest();
            StringBuffer sb = new StringBuffer();
            for (int i = 0; i < thedigest.length; i++)
                sb.append(Integer.toString((thedigest[i] & 0xff) + 0x100, 16).substring(1));
            context.write(new Text(sb.toString()), new Text(line));
        }
    }

    public static class Reduce extends Reducer<Text, Text, Text, Text> {

        public void reduce(Text key, Iterable<Text> values, Context context)
                throws IOException, InterruptedException {
            for (Text val : values) {
                context.write(key, val);
            }

        }
    }

    public static void main(String[] args) throws Exception {
        Configuration conf = new Configuration();

        Job job = new Job(conf, "PrepareInput");
        job.setJarByClass(PrepareInput.class);

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

        job.setMapperClass(Map.class);
        job.setReducerClass(Reduce.class);

        job.setInputFormatClass(TextInputFormat.class);
        job.setOutputFormatClass(TextOutputFormat.class);

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

        job.setNumReduceTasks(1);
        job.waitForCompletion(true);
    }

}