Hadoop 排序

/**
* int的key按照降序排列
*
* @author whf
*
*/
public class IntKeyDescComparator extends WritableComparator {

protected IntKeyDescComparator() {
super(IntWritable.class, true);

}

@Override
public int compare(WritableComparable a, WritableComparable b) {
return -super.compare(a, b);
}

}