org.apache.commons.io.monitor
Class FileAlterationMonitor

java.lang.Object
  org.apache.commons.io.monitor.FileAlterationMonitor

All Implemented Interfaces:

java.lang.Runnable

public final class FileAlterationMonitor
extends java.lang.Object
implements java.lang.Runnable

A runnable that spawns a monitoring thread triggering any registered FileAlterationObserver at a specified interval.

Since:

2.0

Version:

$Id: FileAlterationMonitor.java 1304052 2012-03-22 20:55:29Z ggregory $

See Also:

FileAlterationObserver

Field Summary

private long	interval
private java.util.List<FileAlterationObserver>	observers
private boolean	running
private java.lang.Thread	thread
private java.util.concurrent.ThreadFactory	threadFactory

Constructor Summary

FileAlterationMonitor()
Construct a monitor with a default interval of 10 seconds.

FileAlterationMonitor(long interval)
Construct a monitor with the specified interval.

FileAlterationMonitor(long interval, FileAlterationObserver... observers)
Construct a monitor with the specified interval and set of observers.

Method Summary

void	addObserver(FileAlterationObserver observer) Add a file system observer to this monitor.
long	getInterval() Return the interval.
java.lang.Iterable<FileAlterationObserver>	getObservers() Returns the set of FileAlterationObserver registered with this monitor.
void	removeObserver(FileAlterationObserver observer) Remove a file system observer from this monitor.
void	run() Run.
void	setThreadFactory(java.util.concurrent.ThreadFactory threadFactory) Set the thread factory.
void	start() Start monitoring.
void	stop() Stop monitoring.
void	stop(long stopInterval) Stop monitoring.

Methods inherited from class java.lang.Object

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

Field Detail

interval

private final long interval

observers

private final java.util.List<FileAlterationObserver> observers

thread

private java.lang.Thread thread

threadFactory

private java.util.concurrent.ThreadFactory threadFactory

running

private volatile boolean running

Constructor Detail

FileAlterationMonitor

public FileAlterationMonitor()

Construct a monitor with a default interval of 10 seconds.

FileAlterationMonitor

public FileAlterationMonitor(long interval)

Construct a monitor with the specified interval.

Parameters:

interval - The amount of time in miliseconds to wait between checks of the file system

FileAlterationMonitor

public FileAlterationMonitor(long interval,
                             FileAlterationObserver... observers)

Construct a monitor with the specified interval and set of observers.

Parameters:

interval - The amount of time in miliseconds to wait between checks of the file system

observers - The set of observers to add to the monitor.

Method Detail

getInterval

public long getInterval()

Return the interval.

Returns:

the interval

setThreadFactory

public void setThreadFactory(java.util.concurrent.ThreadFactory threadFactory)

Set the thread factory.

Parameters:

threadFactory - the thread factory

addObserver

public void addObserver(FileAlterationObserver observer)

Add a file system observer to this monitor.

Parameters:

observer - The file system observer to add

removeObserver

public void removeObserver(FileAlterationObserver observer)

Remove a file system observer from this monitor.

Parameters:

observer - The file system observer to remove

getObservers

public java.lang.Iterable<FileAlterationObserver> getObservers()

Returns the set of FileAlterationObserver registered with this monitor.

Returns:

The set of FileAlterationObserver

start

public void start()
           throws java.lang.Exception

Start monitoring.

Throws:

java.lang.Exception - if an error occurs initializing the observer

stop

public void stop()
          throws java.lang.Exception

Stop monitoring.

Throws:

java.lang.Exception - if an error occurs initializing the observer

stop

public void stop(long stopInterval)
          throws java.lang.Exception

Stop monitoring.

Parameters:

stopInterval - the amount of time in milliseconds to wait for the thread to finish. A value of zero will wait until the thread is finished (see Thread.join(long)).

Throws:

java.lang.Exception - if an error occurs initializing the observer

Since:

2.1

run

public void run()

Run.

Specified by:

run in interface java.lang.Runnable