org.apache.hadoop.contrib.index.example

Class RoundRobinDistributionPolicy

java.lang.Object

org.apache.hadoop.contrib.index.example.RoundRobinDistributionPolicy

All Implemented Interfaces:

IDistributionPolicy

public class RoundRobinDistributionPolicy
extends java.lang.Object
implements IDistributionPolicy

Choose a shard for each insert in a round-robin fashion. Choose all the shards for each delete because we don't know where it is stored.

Constructor Summary

Constructors

Constructor and Description
RoundRobinDistributionPolicy()

Method Summary

Methods

Modifier and Type	Method and Description
int	chooseShardForDelete(DocumentID key) Choose a shard or all shards to send a delete request.
int	chooseShardForInsert(DocumentID key) Choose a shard to send an insert request.
void	init(Shard[] shards) Initialization.

Methods inherited from class java.lang.Object

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

Constructor Detail

RoundRobinDistributionPolicy

public RoundRobinDistributionPolicy()

Method Detail

init

public void init(Shard[] shards)

Description copied from interface: IDistributionPolicy

Initialization. It must be called before any chooseShard() is called.

Specified by:

init in interface IDistributionPolicy

chooseShardForInsert

public int chooseShardForInsert(DocumentID key)

Description copied from interface: IDistributionPolicy

Choose a shard to send an insert request.

Specified by:

chooseShardForInsert in interface IDistributionPolicy

Returns:

the index of the chosen shard

chooseShardForDelete

public int chooseShardForDelete(DocumentID key)

Description copied from interface: IDistributionPolicy

Choose a shard or all shards to send a delete request. E.g. a round-robin distribution policy would send a delete request to all the shards. -1 represents all the shards.

Specified by:

chooseShardForDelete in interface IDistributionPolicy

Returns:

the index of the chosen shard, -1 if all the shards are chosen