WordCountReducer.java

WordCountReducer.java

package com.spnotes.hadoop;

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

import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Reducer;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class WordCountReducer extends Reducer<Text, IntWritable, Text, IntWritable>{
	Logger logger = LoggerFactory.getLogger(WordCountReducer.class);

	@Override
	protected void reduce(Text key, Iterable<IntWritable> values,
			Context context)
			throws IOException, InterruptedException {
		logger.debug("Entering WordCountReducer.reduce() " + this);
		
		int sum = 0;
		Iterator<IntWritable> valuesIt = values.iterator();
		while(valuesIt.hasNext()){
			sum = sum + valuesIt.next().get();
		}
		logger.debug(key + " -> " + sum);
		context.write(key, new IntWritable(sum));
		logger.debug("Exiting WordCountReducer.reduce()");
	}

	
}