ClassAverage.java Source code

Introduction

Here is the source code for ClassAverage.java

Source

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

import org.apache.hadoop.conf.Configuration;
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;

/*
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/**
 *
 * @author Santipab
 */
public class ClassAverage {

    private static class TokenizerMapper extends Mapper<Object, Text, Text, IntWritable> {
        private final static IntWritable one = new IntWritable(1);

        private Double val = 0.0;

        public void map(Object key, Text value, Context context) throws IOException, InterruptedException {
            String[] itr = value.toString().split("\n");

            //word.set(itr.nextToken());
            //context.write(word, one);

        }
    }

    public static class DoubleCalcReducer extends Reducer<Text, IntWritable, Text, IntWritable> {

        private IntWritable result = new IntWritable();

        public void reduce(Text key, Iterable<IntWritable> values, Reducer.Context context)
                throws IOException, InterruptedException {
            int sum = 0;
            for (IntWritable val : values) {
                sum += val.get();
            }
            result.set(sum);
            context.write(key, result);
        }
    }

    public static void main(String[] args) throws Exception {
        Configuration conf = new Configuration();
        Job job = new Job(conf, "Class Average");

        job.setJarByClass(ClassAverage.class);
        job.setMapperClass(TokenizerMapper.class);
        job.setCombinerClass(DoubleCalcReducer.class);
        job.setReducerClass(DoubleCalcReducer.class);

        job.setOutputKeyClass(Text.class);

    }
}