Package org.springframework.integration.file.filters

Class AcceptOnceFileListFilter<F>

java.lang.Object

org.springframework.integration.file.filters.AbstractFileListFilter<F>

org.springframework.integration.file.filters.AcceptOnceFileListFilter<F>

Type Parameters:

F - the file type.

All Implemented Interfaces:

FileListFilter<F>, ResettableFileListFilter<F>, ReversibleFileListFilter<F>

public class AcceptOnceFileListFilter<F>
extends AbstractFileListFilter<F>
implements ReversibleFileListFilter<F>, ResettableFileListFilter<F>

FileListFilter that passes files only one time. This can conveniently be used to prevent duplication of files, as is done in FileReadingMessageSource.

This implementation is thread safe.

Author:

Iwein Fuld, Josh Long, Gary Russell, Artem Bilan, Christian Tzolov

Constructor Summary

Constructors

Constructor	Description
AcceptOnceFileListFilter()	Creates an AcceptOnceFileListFilter based on an unbounded queue.
AcceptOnceFileListFilter(int maxCapacity)	Creates an AcceptOnceFileListFilter that is based on a bounded queue.

Method Summary

Modifier and Type	Method	Description
boolean	accept(F file)	Subclasses must implement this method.
boolean	remove(F fileToRemove)	Remove the specified file from the filter, so it will pass on the next attempt.
void	rollback(F file, List<F> files)	Indicate that not all files previously passed by this filter (in FileListFilter.filterFiles(Object[]) have been processed; the file must be in the list of files; it, and all files after it, will be considered to have not been processed and will be considered next time.

Methods inherited from class org.springframework.integration.file.filters.AbstractFileListFilter

filterFiles, supportsSingleFileFiltering

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.springframework.integration.file.filters.FileListFilter

filterFiles, isForRecursion, supportsSingleFileFiltering

Constructor Details

AcceptOnceFileListFilter

public AcceptOnceFileListFilter(int maxCapacity)

Creates an AcceptOnceFileListFilter that is based on a bounded queue. If the queue overflows, files that fall out will be passed through this filter again if passed to the AbstractFileListFilter.filterFiles(Object[])

Parameters:

maxCapacity - the maximum number of Files to maintain in the 'seen' queue.

AcceptOnceFileListFilter

public AcceptOnceFileListFilter()

Creates an AcceptOnceFileListFilter based on an unbounded queue.

Method Details

accept

public boolean accept(F file)

Description copied from class: AbstractFileListFilter

Subclasses must implement this method.

Specified by:

accept in interface FileListFilter<F>

Specified by:

accept in class AbstractFileListFilter<F>

Parameters:

file - The file.

Returns:

true if the file passes the filter.

See Also:

• FileListFilter.supportsSingleFileFiltering()

rollback

public void rollback(F file,
 List<F> files)

Description copied from interface: ReversibleFileListFilter

Indicate that not all files previously passed by this filter (in FileListFilter.filterFiles(Object[]) have been processed; the file must be in the list of files; it, and all files after it, will be considered to have not been processed and will be considered next time.

Specified by:

rollback in interface ReversibleFileListFilter<F>

Parameters:

file - the file which failed.

files - the list of files that were returned by FileListFilter.filterFiles(Object[]).

remove

public boolean remove(F fileToRemove)

Description copied from interface: ResettableFileListFilter

Remove the specified file from the filter, so it will pass on the next attempt.

Specified by:

remove in interface ResettableFileListFilter<F>

Parameters:

fileToRemove - the element to remove.

Returns:

true if the file was removed as a result of this call.