org.springframework.batch.item.support

Class CompositeItemWriter<T>

java.lang.Object

org.springframework.batch.item.support.CompositeItemWriter<T>

All Implemented Interfaces:

ItemStream, ItemStreamWriter<T>, ItemWriter<T>, org.springframework.beans.factory.InitializingBean

public class CompositeItemWriter<T>
extends java.lang.Object
implements ItemStreamWriter<T>, org.springframework.beans.factory.InitializingBean

Calls a collection of ItemWriters in fixed-order sequence.

The implementation is thread-safe if all delegates are thread-safe.

Author:

Robert Kasanicky, Dave Syer

Constructor Summary

Constructors

Constructor and Description
CompositeItemWriter()

Method Summary

Modifier and Type	Method and Description
void	afterPropertiesSet()
void	close() If any resources are needed for the stream to operate they need to be destroyed here.
void	open(ExecutionContext executionContext) Open the stream for the provided ExecutionContext.
void	setDelegates(java.util.List<ItemWriter<? super T>> delegates) The list of item writers to use as delegates.
void	setIgnoreItemStream(boolean ignoreItemStream) Establishes the policy whether to call the open, close, or update methods for the item writer delegates associated with the CompositeItemWriter.
void	update(ExecutionContext executionContext) Indicates that the execution context provided during open is about to be saved.
void	write(java.util.List<? extends T> item) Process the supplied data element.

Methods inherited from class java.lang.Object

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

Constructor Detail

CompositeItemWriter

public CompositeItemWriter()

Method Detail

setIgnoreItemStream

public void setIgnoreItemStream(boolean ignoreItemStream)

Establishes the policy whether to call the open, close, or update methods for the item writer delegates associated with the CompositeItemWriter.

Parameters:

ignoreItemStream - if false the delegates' open, close, or update methods will be called when the corresponding methods on the CompositeItemWriter are called. If true the delegates' open, close, nor update methods will not be called (default is false).

write

public void write(java.util.List<? extends T> item)
           throws java.lang.Exception

Description copied from interface: ItemWriter

Process the supplied data element. Will not be called with any null items in normal operation.

Specified by:

write in interface ItemWriter<T>

Parameters:

item - items to be written

Throws:

java.lang.Exception - if there are errors. The framework will catch the exception and convert or rethrow it as appropriate.

afterPropertiesSet

public void afterPropertiesSet()
                        throws java.lang.Exception

Specified by:

afterPropertiesSet in interface org.springframework.beans.factory.InitializingBean

Throws:

java.lang.Exception

setDelegates

public void setDelegates(java.util.List<ItemWriter<? super T>> delegates)

The list of item writers to use as delegates. Items are written to each of the delegates.

Parameters:

delegates - the list of delegates to use. The delegates list must not be null nor be empty.

close

public void close()
           throws ItemStreamException

Description copied from interface: ItemStream

If any resources are needed for the stream to operate they need to be destroyed here. Once this method has been called all other methods (except open) may throw an exception.

Specified by:

close in interface ItemStream

Throws:

ItemStreamException

open

public void open(ExecutionContext executionContext)
          throws ItemStreamException

Description copied from interface: ItemStream

Open the stream for the provided ExecutionContext.

Specified by:

open in interface ItemStream

Parameters:

executionContext - current step's ExecutionContext. Will be the executionContext from the last run of the step on a restart.

Throws:

ItemStreamException

update

public void update(ExecutionContext executionContext)
            throws ItemStreamException

Description copied from interface: ItemStream

Indicates that the execution context provided during open is about to be saved. If any state is remaining, but has not been put in the context, it should be added here.

Specified by:

update in interface ItemStream

Parameters:

executionContext - to be updated

Throws:

ItemStreamException