Package org.springframework.batch.item.file

Class ResourcesItemReader

java.lang.Object

org.springframework.batch.item.ItemStreamSupport

org.springframework.batch.item.support.AbstractItemStreamItemReader<org.springframework.core.io.Resource>

org.springframework.batch.item.file.ResourcesItemReader

All Implemented Interfaces:

ItemReader<org.springframework.core.io.Resource>, ItemStream, ItemStreamReader<org.springframework.core.io.Resource>

public class ResourcesItemReader
extends AbstractItemStreamItemReader<org.springframework.core.io.Resource>

ItemReader which produces Resource instances from an array. This can be used conveniently with a configuration entry that injects a pattern (e.g. mydir/*.txt, which can then be converted by Spring to an array of Resources by the ApplicationContext.

Thread-safe between calls to open(ExecutionContext). The ExecutionContext is not accurate in a multi-threaded environment, so do not rely on that data for restart (i.e. always open with a fresh context).

Since:

2.1

Author:

Dave Syer, Mahmoud Ben Hassine

See Also:

• ResourceArrayPropertyEditor

Constructor Summary

Constructors

Constructor	Description
ResourcesItemReader()

Method Summary

Modifier and Type	Method	Description
void	open(ExecutionContext executionContext)	No-op.
org.springframework.core.io.Resource	read()	Increments a counter and returns the next Resource instance from the input, or null if none remain.
void	setResources(org.springframework.core.io.Resource[] resources)	The resources to serve up as items.
void	update(ExecutionContext executionContext)	Return empty ExecutionContext.

Methods inherited from class org.springframework.batch.item.ItemStreamSupport

close, getExecutionContextKey, getName, setExecutionContextName, setName

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.springframework.batch.item.ItemStream

close

Constructor Details

ResourcesItemReader

public ResourcesItemReader()

Method Details

setResources

public void setResources(org.springframework.core.io.Resource[] resources)

The resources to serve up as items. Hint: use a pattern to configure.

Parameters:

resources - the resources

read

@Nullable
public org.springframework.core.io.Resource read()
                                          throws Exception

Increments a counter and returns the next Resource instance from the input, or null if none remain.

Returns:

T the item to be processed or null if the data source is exhausted

Throws:

ParseException - if there is a problem parsing the current record (but the next one may still be valid)

NonTransientResourceException - if there is a fatal exception in the underlying resource. After throwing this exception implementations should endeavour to return null from subsequent calls to read.

UnexpectedInputException - if there is an uncategorised problem with the input data. Assume potentially transient, so subsequent calls to read might succeed.

Exception - if an there is a non-specific error.

open

public void open(ExecutionContext executionContext)
          throws ItemStreamException

Description copied from class: ItemStreamSupport

No-op.

Specified by:

open in interface ItemStream

Overrides:

open in class ItemStreamSupport

Parameters:

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

Throws:

ItemStreamException

See Also:

• ItemStream.open(ExecutionContext)

update

public void update(ExecutionContext executionContext)
            throws ItemStreamException

Description copied from class: ItemStreamSupport

Return empty ExecutionContext.

Specified by:

update in interface ItemStream

Overrides:

update in class ItemStreamSupport

Parameters:

executionContext - to be updated

Throws:

ItemStreamException

See Also:

• ItemStream.update(ExecutionContext)