import java.util.*;
import java.io.*;

import org.apache.hadoop.fs.Path;
import org.apache.hadoop.conf.*;
import org.apache.hadoop.io.*;
import org.apache.hadoop.mapred.*;
import org.apache.hadoop.util.*;

public class WordCount{
	
	public static class Map extends MapReduceBase implements Mapper<LongWritable, Text, Text, IntWritable> {
		
		
		public void map(LongWritable key, Text value, OutputCollector<Text, IntWritable> output, Reporter report) throws IOException {
			
			// Program logic
			String line = value.toString();
			Scanner scanner = new Scanner(line);
			
			while (scanner.hasNext()) {
				String token = scanner.next();
				
				Text word = new Text();
				word.set(token);
				
				output.collect(word, new IntWritable(1));
				
				
			}
	

		}
		
	}
	
	public static class Reduce extends MapReduceBase implements Reducer<Text, IntWritable, Text, LongWritable> {
		
		public void reduce(Text key, Iterator<IntWritable> values, OutputCollector<Text, LongWritable> output, Reporter report) throws IOException {
			
			
			int count = 0;
			
			// Program logic
			
			while (values.hasNext()) {
				count += values.next().get();
			}
			
			//Emit final key and value
			output.collect(key, new LongWritable(count));
			
			
		}
		
		
		
	}
	
	public static void main(String args[]) throws Exception{
		
		
		JobConf conf = new JobConf(WordCount.class);
		conf.setJobName("WordCount Example!");
			
		conf.setMapperClass(Map.class);
		conf.setReducerClass(Reduce.class);
		

		conf.setOutputKeyClass(Text.class);
		conf.setOutputValueClass(IntWritable.class);
		
		conf.setNumReduceTasks(1);
		
		FileInputFormat.setInputPaths(conf, new Path(args[0]));
		FileOutputFormat.setOutputPath(conf, new Path(args[1]));
		
		JobClient.runJob(conf);
		
		
		 
	}
	
	
	
	
}