org.springframework.batch.integration.chunk

Class RemoteChunkHandlerFactoryBean<T>

java.lang.Object

org.springframework.batch.integration.chunk.RemoteChunkHandlerFactoryBean<T>

All Implemented Interfaces:

org.springframework.beans.factory.FactoryBean<ChunkHandler<T>>

public class RemoteChunkHandlerFactoryBean<T>
extends java.lang.Object
implements org.springframework.beans.factory.FactoryBean<ChunkHandler<T>>

Convenient factory bean for a chunk handler that also converts an existing chunk-oriented step into a remote chunk master. The idea is to lift the existing chunk processor out of a Step that works locally, and replace it with a one that writes chunks into a message channel. The existing step hands its business chunk processing responsibility over to the handler produced by the factory, which then needs to be set up as a worker on the other end of the channel the chunks are being sent to. Once this chunk handler is installed the application is playing the role of both the manager and the worker listeners in the Remote Chunking pattern for the Step in question.

Author:

Dave Syer, Mahmoud Ben Hassine

Field Summary

Fields inherited from interface org.springframework.beans.factory.FactoryBean

OBJECT_TYPE_ATTRIBUTE

Constructor Summary

Constructors

Constructor and Description
RemoteChunkHandlerFactoryBean()

Method Summary

Modifier and Type	Method and Description
ChunkHandler<T>	getObject() Builds a ChunkHandler from the ChunkProcessor extracted from the step provided.
java.lang.Class<?>	getObjectType() The type of object created by this factory.
boolean	isSingleton() Optimization for the bean factory (always returns true).
void	setChunkWriter(ItemWriter<T> chunkWriter) The item writer to be injected into the step.
void	setStep(TaskletStep step) The local step that is to be converted to a remote chunk master.
void	setStepContributionSource(StepContributionSource stepContributionSource) A source of StepContribution instances coming back from remote workers.
protected void	updateStepContribution(StepContribution contribution, StepContributionSource stepContributionSource) Update a StepContribution with all the data from a StepContributionSource.

Methods inherited from class java.lang.Object

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

Constructor Detail

RemoteChunkHandlerFactoryBean

public RemoteChunkHandlerFactoryBean()

Method Detail

setStep

public void setStep(TaskletStep step)

The local step that is to be converted to a remote chunk master.

Parameters:

step - the step to set

setChunkWriter

public void setChunkWriter(ItemWriter<T> chunkWriter)

The item writer to be injected into the step. Its responsibility is to send chunks of items to remote workers. Usually in practice it will be a ChunkMessageChannelItemWriter.

Parameters:

chunkWriter - the chunk writer to set

setStepContributionSource

public void setStepContributionSource(StepContributionSource stepContributionSource)

A source of StepContribution instances coming back from remote workers.

Parameters:

stepContributionSource - the step contribution source to set (defaults to the chunk writer)

getObjectType

public java.lang.Class<?> getObjectType()

The type of object created by this factory. Returns ChunkHandler class.

Specified by:

getObjectType in interface org.springframework.beans.factory.FactoryBean<ChunkHandler<T>>

See Also:

FactoryBean.getObjectType()

isSingleton

public boolean isSingleton()

Optimization for the bean factory (always returns true).

Specified by:

isSingleton in interface org.springframework.beans.factory.FactoryBean<ChunkHandler<T>>

See Also:

FactoryBean.isSingleton()

getObject

public ChunkHandler<T> getObject()
                          throws java.lang.Exception

Builds a ChunkHandler from the ChunkProcessor extracted from the step provided. Also modifies the step to send chunks to the chunk handler via the chunk writer.

Specified by:

getObject in interface org.springframework.beans.factory.FactoryBean<ChunkHandler<T>>

Throws:

java.lang.Exception

See Also:

FactoryBean.getObject()

updateStepContribution

protected void updateStepContribution(StepContribution contribution,
                                      StepContributionSource stepContributionSource)

Update a StepContribution with all the data from a StepContributionSource. The filter and write counts plus the exit status will be updated to reflect the data in the source.

Parameters:

contribution - the current contribution

stepContributionSource - a source of StepContributions