org.apache.hadoop.examples

类 SecondarySort.FirstPartitioner

java.lang.Object

org.apache.hadoop.mapreduce.Partitioner<SecondarySort.IntPair,IntWritable>

org.apache.hadoop.examples.SecondarySort.FirstPartitioner

封闭类:

SecondarySort

public static class SecondarySort.FirstPartitioner
extends Partitioner<SecondarySort.IntPair,IntWritable>

Partition based on the first part of the pair.

构造器概要

构造器

构造器和说明
SecondarySort.FirstPartitioner()

方法概要

方法

限定符和类型	方法和说明
int	getPartition(SecondarySort.IntPair key, IntWritable value, int numPartitions) Get the partition number for a given key (hence record) given the total number of partitions i.e. number of reduce-tasks for the job.

从类继承的方法 java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

构造器详细资料

SecondarySort.FirstPartitioner

public SecondarySort.FirstPartitioner()

方法详细资料

getPartition

public int getPartition(SecondarySort.IntPair key,
               IntWritable value,
               int numPartitions)

从类复制的说明: Partitioner

Get the partition number for a given key (hence record) given the total number of partitions i.e. number of reduce-tasks for the job.

Typically a hash function on a all or a subset of the key.

指定者:

getPartition 在类中 Partitioner<SecondarySort.IntPair,IntWritable>

参数:

key - the key to be partioned.

value - the entry value.

numPartitions - the total number of partitions.

返回:

the partition number for the key.