cityhubpartitioningcountry.CityHubPartitioning.java Source code

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Here is the source code for cityhubpartitioningcountry.CityHubPartitioning.java

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package cityhubpartitioningcountry;

import java.io.IOException;
import org.apache.hadoop.conf.Configurable;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.NullWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Job;
import org.apache.hadoop.mapreduce.Mapper;
import org.apache.hadoop.mapreduce.Partitioner;
import org.apache.hadoop.mapreduce.Reducer;
import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;

/**
 *
 * @author pranali
 */
public class CityHubPartitioning {

    public static class PartitionMonthMapper extends Mapper<Object, Text, Text, Text> {
        private Text country = new Text();

        public void map(Object key, Text value, Context context) throws IOException, InterruptedException {
            String[] tokens = value.toString().split(",");
            String mn = tokens[1].trim();
            country.set(mn);
            context.write(country, value);

        }
    }

    public static class PartitionCountryPartitioner extends Partitioner<Text, Text> implements Configurable {
        private Configuration conf = null;
        private int ret = 0;

        @Override
        public int getPartition(Text key, Text value, int i) {
            if (key.toString().startsWith("A")) {
                return 0;

            } else if (key.toString().startsWith("B")) {
                return 1;

            } else if (key.toString().startsWith("C")) {
                return 2;

            } else if (key.toString().startsWith("D")) {
                return 3;

            } else if (key.toString().startsWith("E")) {
                return 4;

            } else if (key.toString().startsWith("F")) {
                return 5;

            } else if (key.toString().startsWith("G")) {
                return 6;

            } else if (key.toString().startsWith("H")) {
                return 7;

            } else if (key.toString().startsWith("I")) {
                return 8;

            } else if (key.toString().startsWith("J")) {
                return 9;

            } else if (key.toString().startsWith("K")) {
                return 10;

            } else if (key.toString().startsWith("L")) {
                return 11;

            } else if (key.toString().startsWith("M")) {
                return 12;

            } else if (key.toString().startsWith("N")) {
                return 13;

            } else if (key.toString().startsWith("O")) {
                return 14;

            } else if (key.toString().startsWith("P")) {
                return 15;

            } else if (key.toString().startsWith("Q")) {
                return 16;

            } else if (key.toString().startsWith("R")) {
                return 17;

            } else if (key.toString().startsWith("S")) {
                return 18;

            } else if (key.toString().startsWith("T")) {
                return 19;

            } else if (key.toString().startsWith("U")) {
                return 20;

            } else if (key.toString().startsWith("V")) {
                return 21;

            } else if (key.toString().startsWith("W")) {
                return 22;

            } else if (key.toString().startsWith("X")) {
                return 23;

            } else if (key.toString().startsWith("Y")) {
                return 24;

            } else if (key.toString().startsWith("Z")) {
                return 25;

            } else {
                return 26;
            }

        }

        @Override
        public void setConf(Configuration conf) {
            this.conf = conf;
        }

        @Override
        public Configuration getConf() {
            return conf;
        }

    }

    public static class countryReducer extends Reducer<Text, Text, Text, NullWritable> {
        protected void reduce(Text key, Iterable<Text> values, Context context)
                throws IOException, InterruptedException {
            for (Text t : values) {
                context.write(t, NullWritable.get());

            }
        }
    }

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) throws IOException, InterruptedException, ClassNotFoundException {
        Configuration conf = new Configuration();
        Job job = Job.getInstance(conf, "partitioner");
        job.setJarByClass(CityHubPartitioning.class);
        job.setMapperClass(PartitionMonthMapper.class);
        job.setReducerClass(countryReducer.class);
        job.setMapOutputKeyClass(Text.class);
        job.setMapOutputValueClass(Text.class);

        job.setPartitionerClass(PartitionCountryPartitioner.class);

        job.setNumReduceTasks(27);
        job.setOutputKeyClass(Text.class);
        job.setOutputValueClass(NullWritable.class);
        FileInputFormat.addInputPath(job, new Path(args[0]));
        FileOutputFormat.setOutputPath(job, new Path(args[1]));
        System.exit(job.waitForCompletion(true) ? 0 : 1);
    }
}