org.springframework.batch.item.data

Class MongoItemWriter<T>

java.lang.Object

org.springframework.batch.item.data.MongoItemWriter<T>

All Implemented Interfaces:

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

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

A ItemWriter implementation that writes to a MongoDB store using an implementation of Spring Data's MongoOperations. Since MongoDB is not a transactional store, a best effort is made to persist written data at the last moment, yet still honor job status contracts. No attempt to roll back is made if an error occurs during writing.

This writer is thread-safe once all properties are set (normal singleton behavior) so it can be used in multiple concurrent transactions.

Author:

Michael Minella, Parikshit Dutta, Mahmoud Ben Hassine

Constructor Summary

Constructors

Constructor and Description
MongoItemWriter()

Method Summary

Modifier and Type	Method and Description
void	afterPropertiesSet()
protected void	doWrite(java.util.List<? extends T> items) Performs the actual write to the store via the template.
protected org.springframework.data.mongodb.core.MongoOperations	getTemplate() Get the MongoOperations to be used to save items to be written.
void	setCollection(java.lang.String collection) Set the name of the Mongo collection to be written to.
void	setDelete(boolean delete) Indicates if the items being passed to the writer are to be saved or removed from the data store.
void	setTemplate(org.springframework.data.mongodb.core.MongoOperations template) Set the MongoOperations to be used to save items to be written.
void	write(java.util.List<? extends T> items) If a transaction is active, buffer items to be written just before commit.

Methods inherited from class java.lang.Object

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

Constructor Detail

MongoItemWriter

public MongoItemWriter()

Method Detail

setDelete

public void setDelete(boolean delete)

Indicates if the items being passed to the writer are to be saved or removed from the data store. If set to false (default), the items will be saved. If set to true, the items will be removed.

Parameters:

delete - removal indicator

setTemplate

public void setTemplate(org.springframework.data.mongodb.core.MongoOperations template)

Set the MongoOperations to be used to save items to be written.

Parameters:

template - the template implementation to be used.

getTemplate

protected org.springframework.data.mongodb.core.MongoOperations getTemplate()

Get the MongoOperations to be used to save items to be written. This can be called by a subclass if necessary.

Returns:

template the template implementation to be used.

setCollection

public void setCollection(java.lang.String collection)

Set the name of the Mongo collection to be written to.

Parameters:

collection - the name of the collection.

write

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

If a transaction is active, buffer items to be written just before commit. Otherwise write items using the provided template.

Specified by:

write in interface ItemWriter<T>

Parameters:

items - 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.

See Also:

ItemWriter.write(List)

doWrite

protected void doWrite(java.util.List<? extends T> items)

Performs the actual write to the store via the template. This can be overridden by a subclass if necessary.

Parameters:

items - the list of items to be persisted.

afterPropertiesSet

public void afterPropertiesSet()
                        throws java.lang.Exception

Specified by:

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

Throws:

java.lang.Exception