小编dac*_*rmo的帖子

我想通过配置不同的映射，与减速机的输出类型 setMapOutputKeyClass，setMapOutputValueClass，setMapKeyClass，和 setMapValueClass。但是，即使我调用了这些函数，在运行时仍会收到错误消息。

这是我的代码：

package org.myorg;

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

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 Sort {

    public static class Map extends MapReduceBase implements Mapper<LongWritable, Text, Text, IntWritable> {
      private final static IntWritable one = new IntWritable(1);
      private Text word = new Text();

      public void map(LongWritable key, Text value, OutputCollector<Text, IntWritable> output, Reporter reporter) throws IOException {
        String line = value.toString();
        StringTokenizer tokenizer = new StringTokenizer(line);
        while …