Class SimpleChunkProvider<I>
- java.lang.Object
- org.springframework.batch.core.step.item.SimpleChunkProvider<I>
- All Implemented Interfaces:
ChunkProvider<I>
- Direct Known Subclasses:
FaultTolerantChunkProvider
public class SimpleChunkProvider<I> extends java.lang.Object implements ChunkProvider<I>
Simple implementation of the ChunkProvider interface that does basic chunk providing from anItemReader.- Author:
- Dave Syer, Michael Minella, Mahmoud Ben Hassine
- See Also:
ChunkOrientedTasklet
Field Summary
Fields Modifier and Type Field Description protected ItemReader<? extends I>itemReaderprotected org.apache.commons.logging.Loglogger
Constructor Summary
Constructors Constructor Description SimpleChunkProvider(ItemReader<? extends I> itemReader, RepeatOperations repeatOperations)
Method Summary
All Methods Instance Methods Concrete Methods Modifier and Type Method Description protected IdoRead()Surrounds the read call with listener callbacks.protected MulticasterBatchListener<I,?>getListener()voidpostProcess(StepContribution contribution, Chunk<I> chunk)Chunk<I>provide(StepContribution contribution)protected Iread(StepContribution contribution, Chunk<I> chunk)Delegates todoRead().voidregisterListener(StepListener listener)Register a listener for callbacks at the appropriate stages in a process.voidsetListeners(java.util.List<? extends StepListener> listeners)Register someStepListeners with the handler.
Field Detail
logger
protected final org.apache.commons.logging.Log logger
itemReader
protected final ItemReader<? extends I> itemReader
Constructor Detail
SimpleChunkProvider
public SimpleChunkProvider(ItemReader<? extends I> itemReader, RepeatOperations repeatOperations)
Method Detail
setListeners
public void setListeners(java.util.List<? extends StepListener> listeners)
Register someStepListeners with the handler. Each will get the callbacks in the order specified at the correct stage.- Parameters:
listeners- list ofStepListeners.
registerListener
public void registerListener(StepListener listener)
Register a listener for callbacks at the appropriate stages in a process.- Parameters:
listener- aStepListener
getListener
protected MulticasterBatchListener<I,?> getListener()
- Returns:
- the listener
doRead
@Nullable protected final I doRead() throws java.lang.Exception
Surrounds the read call with listener callbacks.- Returns:
- the item or
nullif the data source is exhausted - Throws:
java.lang.Exception- is thrown if error occurs during read.
provide
public Chunk<I> provide(StepContribution contribution) throws java.lang.Exception
- Specified by:
providein interfaceChunkProvider<I>- Throws:
java.lang.Exception
postProcess
public void postProcess(StepContribution contribution, Chunk<I> chunk)
- Specified by:
postProcessin interfaceChunkProvider<I>
read
@Nullable protected I read(StepContribution contribution, Chunk<I> chunk) throws SkipOverflowException, java.lang.Exception
Delegates todoRead(). Subclasses can add additional behaviour (e.g. exception handling).- Parameters:
contribution- the current step execution contributionchunk- the current chunk- Returns:
- a new item for processing or
nullif the data source is exhausted - Throws:
SkipOverflowException- if specifically the chunk is accumulating too much data (e.g. skips) and it wants to force a commit.java.lang.Exception- if there is a generic issue