jakarta.batch.api.chunk

Interface ItemWriter

All Known Implementing Classes:

AbstractItemWriter

public interface ItemWriter

ItemWriter defines the batch artifact that writes to a list of items for chunk processing.

Method Summary

Modifier and Type	Method and Description
Serializable	checkpointInfo() The checkpointInfo method returns the current checkpoint data for this writer.
void	close() The close method marks the end of use of the ItemWriter.
void	open(Serializable checkpoint) The open method prepares the writer to write items.
void	writeItems(List<Object> items) The writeItems method writes a list of item for the current chunk.

Method Detail

open

void open(Serializable checkpoint)
   throws Exception

The open method prepares the writer to write items. The input parameter represents the last checkpoint for this writer in a given job instance. The checkpoint data is defined by this writer and is provided by the checkpointInfo method. The checkpoint data provides the writer whatever information it needs to resume writing items upon restart. A checkpoint value of null is passed upon initial start.

Parameters:

checkpoint - specifies the last checkpoint

Throws:

Exception - is thrown for any errors.

close

void close()
    throws Exception

The close method marks the end of use of the ItemWriter. The writer is free to do any cleanup necessary.

Throws:

Exception - is thrown for any errors.

writeItems

void writeItems(List<Object> items)
         throws Exception

The writeItems method writes a list of item for the current chunk.

Parameters:

items - specifies the list of items to write. This may be an empty list (e.g. if all the items have been filtered out by the ItemProcessor).

Throws:

Exception - is thrown for any errors.

checkpointInfo

Serializable checkpointInfo()
                     throws Exception

The checkpointInfo method returns the current checkpoint data for this writer. It is called before a chunk checkpoint is committed.

Returns:

checkpoint data

Throws:

Exception - is thrown for any errors.