Package org.springframework.integration.file.filters

Class AbstractPersistentAcceptOnceFileListFilter<F>

java.lang.Object

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

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

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

Type Parameters:

F - the file type.

All Implemented Interfaces:

Closeable, AutoCloseable, FileListFilter<F>, ResettableFileListFilter<F>, ReversibleFileListFilter<F>

Direct Known Subclasses:

FileSystemPersistentAcceptOnceFileListFilter, FtpPersistentAcceptOnceFileListFilter, SftpPersistentAcceptOnceFileListFilter

public abstract class AbstractPersistentAcceptOnceFileListFilter<F>
extends AbstractDirectoryAwareFileListFilter<F>
implements ReversibleFileListFilter<F>, ResettableFileListFilter<F>, Closeable

Stores "seen" files in a MetadataStore to survive application restarts. The default key is 'prefix' plus the absolute file name; value is the timestamp of the file. Files are deemed as already 'seen' if they exist in the store and have the same modified time as the current file.

Since:

3.0

Author:

Gary Russell, Artem Bilan

Field Summary

Fields

Modifier and Type	Field	Description
protected Flushable	flushableStore
protected boolean	flushOnUpdate
protected String	prefix
protected ConcurrentMetadataStore	store

Constructor Summary

Constructors

Constructor	Description
AbstractPersistentAcceptOnceFileListFilter(ConcurrentMetadataStore store, String prefix)

Method Summary

Modifier and Type	Method	Description
boolean	accept(F file)	Subclasses must implement this method.
protected String	buildKey(F file)	The default key is the prefix plus the full filename.
void	close()
protected abstract String	fileName(F file)
protected boolean	fileStillExists(F file)	Check if the file still exists; default implementation returns true.
protected void	flushIfNeeded()	Flush the store if it's a Flushable and flushOnUpdate is true.
protected boolean	isEqual(F file, String value)	Override this method if you wish to use something other than the modified timestamp to determine equality.
protected abstract long	modified(F file)
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.
void	setFlushOnUpdate(boolean flushOnUpdate)	Determine whether the metadataStore should be flushed on each update (if Flushable).

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

alwaysAccept, isDirectory, isForRecursion, setAlwaysAcceptDirectories, setForRecursion

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

Field Details

store

protected final ConcurrentMetadataStore store

prefix

protected final String prefix

flushableStore

@Nullable protected final Flushable flushableStore

flushOnUpdate

protected boolean flushOnUpdate

Constructor Details

AbstractPersistentAcceptOnceFileListFilter

public AbstractPersistentAcceptOnceFileListFilter(ConcurrentMetadataStore store, String prefix)

Method Details

setFlushOnUpdate

public void setFlushOnUpdate(boolean flushOnUpdate)

Determine whether the metadataStore should be flushed on each update (if Flushable).

Parameters:

flushOnUpdate - true to flush.

Since:

4.1.5

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()

fileStillExists

protected boolean fileStillExists(F file)

Check if the file still exists; default implementation returns true.

Parameters:

file - the file.

Returns:

true if the filter should return true.

Since:

4.3.19

rollback

public 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.

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[]).

Since:

4.0.4

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.

close

public void close() throws IOException

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Throws:

IOException

isEqual

protected boolean isEqual(F file, String value)

Override this method if you wish to use something other than the modified timestamp to determine equality.

Parameters:

file - The file.

value - The current value for the key in the store.

Returns:

true if equal.

buildKey

protected String buildKey(F file)

The default key is the prefix plus the full filename.

Parameters:

file - The file.

Returns:

The key.

flushIfNeeded

protected void flushIfNeeded()

Flush the store if it's a Flushable and flushOnUpdate is true.

Since:

1.4.5

modified

protected abstract long modified(F file)

fileName

protected abstract String fileName(F file)