package demos;

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

import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.BooleanWritable;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapred.FileInputFormat;
import org.apache.hadoop.mapred.FileOutputFormat;
import org.apache.hadoop.mapred.JobClient;
import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.mapred.MapReduceBase;
import org.apache.hadoop.mapred.Mapper;
import org.apache.hadoop.mapred.OutputCollector;
import org.apache.hadoop.mapred.Reducer;
import org.apache.hadoop.mapred.Reporter;

public class SumReducer<A> extends MapReduceBase 
implements Reducer<A, IntWritable, A, IntWritable>{

	private IntWritable result = new IntWritable();
	
	public void reduce(A key, Iterator<IntWritable> values, OutputCollector<A, IntWritable> output, Reporter reporter)
			throws IOException {
		int sum = 0;
		
		while (values.hasNext()) {
			sum += values.next().get();
		}
		
		result.set(sum);
		output.collect(key, result);
	}
}