CountVotes.java

import java.io.IOException;
import java.util.StringTokenizer;
import java.util.ArrayList;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Mapper;
import org.apache.hadoop.mapreduce.Reducer;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.mapreduce.Job;
import org.apache.hadoop.mapreduce.lib.input.TextInputFormat;
import org.apache.hadoop.mapreduce.lib.output.TextOutputFormat;
import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
import org.apache.hadoop.fs.Path;

public class CountVotes {
	public static class Map extends Mapper<LongWritable, Text, Text, IntWritable> {
		public void map(LongWritable key, Text value, Context context) throws IOException, InterruptedException {
			String line = value.toString();
			StringTokenizer tokenizer = new StringTokenizer(line);
            ArrayList<String> tokens = new ArrayList<>();
			while (tokenizer.hasMoreTokens()) {
				tokens.add(tokenizer.nextToken())
			}
            value.set(tokens[5]);
			context.write(value, new IntWritable(1));
		}
	}

	public static class Reduce extends Reducer<Text, IntWritable, Text, IntWritable> {
		public void reduce(Text key, Iterable<IntWritable> values, Context context)
				throws IOException, InterruptedException {
			int sum = 0;
			for (IntWritable x : values) {
				sum += x.get();
			}
			context.write(key, new IntWritable(sum));
		}
	}

	public static void main(String[] args) throws Exception {
		Configuration conf = new Configuration();
		Job job = Job.getInstance(conf, "WordCount");
		job.setJarByClass(WordCount.class);
		job.setMapperClass(Map.class);
		job.setReducerClass(Reduce.class);
		job.setOutputKeyClass(Text.class);
		job.setOutputValueClass(IntWritable.class);
		job.setInputFormatClass(TextInputFormat.class);
		job.setOutputFormatClass(TextOutputFormat.class);
		Path outputPath = new Path(args[1]);
		FileInputFormat.addInputPath(job, new Path(args[0]));
		FileOutputFormat.setOutputPath(job, new Path(args[1]));
		outputPath.getFileSystem(conf).delete(outputPath, true);
		System.exit(job.waitForCompletion(true) ? 0 : 1);
	}
}