adept.mapreduce.MapReduceExample.java Source code

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Here is the source code for adept.mapreduce.MapReduceExample.java

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/*
* Copyright (C) 2016 Raytheon BBN Technologies Corp.
*
* 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 adept.mapreduce;

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

//import org.apache.hadoop.conf.Configuration;
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.Mapper;
//import org.apache.hadoop.mapreduce.Reducer;
//import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;
//import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
import org.apache.hadoop.util.*;
import org.apache.hadoop.mapred.*;
import org.apache.hadoop.conf.*;

public class MapReduceExample extends Configured implements Tool {
    public static class MapClass extends MapReduceBase

            implements Mapper<Text, Text, Text, Text> {

        public void map(Text key, Text value,

                OutputCollector<Text, Text> output,

                Reporter reporter) throws IOException {

            output.collect(value, key);

        }

    }

    public static class Reduce extends MapReduceBase

            implements Reducer<Text, Text, Text, Text> {

        public void reduce(Text key, Iterator<Text> values,

                OutputCollector<Text, Text> output,

                Reporter reporter) throws IOException {

            String csv = "";

            while (values.hasNext()) {

                if (csv.length() > 0)
                    csv += ",";

                csv += values.next().toString();

            }

            output.collect(key, new Text(csv));

        }

    }

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

        Configuration conf = getConf();
        //Configuration conf = new Configuration();

        JobConf job = new JobConf(conf, MapReduceExample.class);

        Path in = new Path(args[0]);

        Path out = new Path(args[1]);

        FileInputFormat.setInputPaths(job, in);

        FileOutputFormat.setOutputPath(job, out);

        job.setJobName("MapReduecExample");

        job.setMapperClass(MapClass.class);

        job.setReducerClass(Reduce.class);

        job.setInputFormat(KeyValueTextInputFormat.class);

        job.setOutputFormat(TextOutputFormat.class);

        job.setOutputKeyClass(Text.class);

        job.setOutputValueClass(Text.class);

        job.set("key.value.separator.in.input.line", ",");

        JobClient.runJob(job);

        return 0;

    }

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

        int res = ToolRunner.run(new Configuration(), new MapReduceExample(), args);

        System.exit(res);

    }
}