Tweets.java

import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Job;
import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;

public class Tweets{

 public static void main (String[] args) throws Exception {
  if (args.length != 2) {
   System.err.println("Usage: Tweets<input path> <output path>");
   System.exit(-1);
  }

 Job job = new Job();
 job.setJarByClass(Tweets.class);
 job.setJobName("Tweets");

 FileInputFormat.addInputPath(job, new Path(args[0]));
 FileOutputFormat.setOutputPath(job, new Path(args[1]));

 job.setMapperClass(TweetsMapper.class);
 job.setReducerClass(TweetsReducer.class);

 job.setOutputKeyClass(Text.class);
 job.setOutputValueClass(IntWritable.class);
 job.setNumReduceTasks(1);

 System.exit(job.waitForCompletion(true) ? 0 : 1);
 }
}