815
WordCount2
WordCount2中我們使用Hadoop框架中給我們提供的類來實現，我們的目的是用最少的代碼來完成同樣的任務
import java.io.IOException;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapred.FileInputFormat;
import org.apache.hadoop.mapred.JobClient;
import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.mapred.FileOutputFormat;
import org.apache.hadoop.mapred.lib.LongSumReducer;
import org.apache.hadoop.mapred.lib.TokenCountMapper;
public class WordCount2 {
public static void main(String[] args) {
JobClient job =new JobClient();
JobConf conf = new JobConf(WordCount2.class);
FileInputFormat.addInputPath(conf, new Path(args[0]));
FileOutputFormat.setOutputPath(conf, new Path(args[1]));
conf.setOutputKeyClass(Text.class);
conf.setOutputValueClass(LongWritable.class);
conf.setMapperClass(TokenCountMapper.class);
conf.setCombinerClass(LongSumReducer.class);
conf.setReducerClass(LongSumReducer.class);
job.setConf(conf);
try {
JobClient.runJob(conf);
} catch (IOException e) {
e.printStackTrace();
}
}
}
最後更新：2017-04-04 07:03:49