我正在写一个需要读3列的map函数。我有一个文本文件：

1234567 12234254 40

如何更改一个简单的wordcountMap器的stringtokenizer，使其能够在使用while循环时读取3行

public static class TokenizerMapper
   extends Mapper<Object, Text, Text, IntWritable>{
private final static IntWritable one = new IntWritable(1);
private Text word = new Text();
public void map(Object key, Text value, Context context
                ) throws IOException, InterruptedException {
  StringTokenizer itr = new StringTokenizer(value.toString());
  while (itr.hasMoreTokens()) {
    word.set(itr.nextToken()); 
    context.write(word, one); 
  }
}

}