Class WeakRefFileListener

java.lang.Object

org.apache.commons.vfs2.util.WeakRefFileListener

All Implemented Interfaces:

FileListener

public class WeakRefFileListener
extends Object
implements FileListener

Wraps a listener with a WeakReference.

Since:

2.0

Field Summary

Fields

Modifier and Type	Field	Description
private final FileSystem	fs
private final WeakReference<FileListener>	listener
private final FileName	name

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	WeakRefFileListener(FileObject file, FileListener listener)

Method Summary

Modifier and Type	Method	Description
void	fileChanged(FileChangeEvent event)	Called when a file is changed.
void	fileCreated(FileChangeEvent event)	Called when a file is created.
void	fileDeleted(FileChangeEvent event)	Called when a file is deleted.
protected FileListener	getListener()	Gets the wrapped listener.
static void	installListener(FileObject file, FileListener listener)	Installs the listener at the given file.

Methods inherited from class Object

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

Field Details

fs

private final FileSystem fs

name

private final FileName name

listener

private final WeakReference<FileListener> listener

Constructor Details

WeakRefFileListener

protected WeakRefFileListener(FileObject file,
 FileListener listener)

Method Details

installListener

public static void installListener(FileObject file,
 FileListener listener)

Installs the listener at the given file.

Parameters:

file - The FileObject to listen on.

listener - The FileListener

getListener

protected FileListener getListener()
                            throws Exception

Gets the wrapped listener. If it is gone, the WeakRefFileListener wrapper will remove itself from the list of listeners.

Returns:

The FileListener.

Throws:

Exception - if an error occurs.

fileCreated

public void fileCreated(FileChangeEvent event)
                 throws Exception

Called when a file is created.

Specified by:

fileCreated in interface FileListener

Parameters:

event - The FileChangeEvent.

Throws:

Exception - if an error occurs.

fileDeleted

public void fileDeleted(FileChangeEvent event)
                 throws Exception

Called when a file is deleted.

Specified by:

fileDeleted in interface FileListener

Parameters:

event - The FileChangeEvent.

Throws:

Exception - if an error occurs.

fileChanged

public void fileChanged(FileChangeEvent event)
                 throws Exception

Called when a file is changed.

This will only happen if you monitor the file using FileMonitor.

Specified by:

fileChanged in interface FileListener

Parameters:

event - The FileChangeEvent.

Throws:

Exception - if an error occurs.