WordAverage

gistfile1.java

package average;

import org.apache.hadoop.conf.Configured;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.FloatWritable;
import org.apache.hadoop.io.IntWritable;
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.util.Tool;
import org.apache.hadoop.util.ToolRunner;

public class WordAverage extends Configured implements Tool {

	public int run(String[] args) throws Exception {
		if (args.length != 2) {
			System.out.printf(
					"Usage: %s [generic options] <input dir> <output dir>\n", getClass().getSimpleName());
			ToolRunner.printGenericCommandUsage(System.out);
			return -1;
		}
		JobConf conf = new JobConf(getConf(), WordAverage.class);
		conf.setJobName(this.getClass().getName());
		FileInputFormat.setInputPaths(conf, new Path(args[0]));
		FileOutputFormat.setOutputPath(conf, new Path(args[1]));
		conf.setMapperClass(AverageMapper.class);
		conf.setReducerClass(AverageReducer.class);
		conf.setMapOutputKeyClass(Text.class);
		conf.setMapOutputValueClass(IntWritable.class);
		conf.setOutputKeyClass(Text.class);
		conf.setOutputValueClass(FloatWritable.class);
		JobClient.runJob(conf);
		return 0;
	}
	public static void main(String[] args) throws Exception {
		int exitCode = ToolRunner.run(new WordAverage(), args);
		System.exit(exitCode);

	}

}