org.apache.hadoop.contrib.index.mapred

类 IndexUpdatePartitioner

java.lang.Object

org.apache.hadoop.contrib.index.mapred.IndexUpdatePartitioner

所有已实现的接口:

JobConfigurable, Partitioner<Shard,IntermediateForm>

public class IndexUpdatePartitioner
extends Object
implements Partitioner<Shard,IntermediateForm>

This partitioner class puts the values of the same key - in this case the same shard - in the same partition.

构造器概要

构造器

构造器和说明
IndexUpdatePartitioner()

方法概要

方法

限定符和类型	方法和说明
void	configure(JobConf job) Initializes a new instance from a JobConf.
int	getPartition(Shard key, IntermediateForm value, int numPartitions) Get the paritition 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

IndexUpdatePartitioner

public IndexUpdatePartitioner()

方法详细资料

getPartition

public int getPartition(Shard key,
               IntermediateForm value,
               int numPartitions)

从接口复制的说明: Partitioner

Get the paritition 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 在接口中 Partitioner<Shard,IntermediateForm>

参数:

key - the key to be paritioned.

value - the entry value.

numPartitions - the total number of partitions.

返回:

the partition number for the key.

configure

public void configure(JobConf job)

从接口复制的说明: JobConfigurable

Initializes a new instance from a JobConf.

指定者:

configure 在接口中 JobConfigurable

参数:

job - the configuration