Properties file change listener java

Signup for news, latest articles and special offers!! Additional menu. ConfigurationException ;. PropertiesConfiguration ;. Before this method can be called a valid file name must have been set. Config Property Successfully Updated. Join the Discussion If you liked this article, then please share it on social media. Other Popular Articles Note that Apache VFS uses a polling algorithm, although it may offer greater functionality.

Also note that the API does not offer a way to determine whether a file has been closed. Java commons-io has a FileAlterationObserver. Similar to commons VFS. The advantag is that it has much less dependencies.

But it uses java File instead of the VFS abstraction layer. I run this snippet of code every time I go to read the properties file, only actually reading the file if it has been modified since the last time I read it. Hope this helps someone. Similar approach is used in Log4J FileWatchdog. Should be in JDK7. Update: Was added to Java SE 7. Chris Janicki offers a link to the relevant Java tutorial. If you are willing to part with some money, JNIWrapper is a useful library with a Winpack, you will be able to get file system events on certain files.

Unfortunately windows only. Otherwise, resorting to native code is not always a bad thing especially when the best on offer is a polling mechanism as against a native event.

I've noticed that Java file system operations can be slow on some computers and can easily affect the application's performance if not handled well. Although this API seems to be focused on dynamic compilation of classes, it also includes classes in its API that monitors file changes. Pretty sure it's cross platform I've used it on mac, linux, and windows. There is a commercial cross-desktop library for files and folders watching called JxFileWatcher.

Similar to the other answers, here's how I did it using File, Timer, and TimerTask to let this run as a background thread polling at set intervals. Polling the last modified file property is a simple yet effective solution though. Just define a class extending my FileChangedWatcher and implement the onModified method:. Stack Overflow for Teams — Collaborate and share knowledge with a private group.

Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. File changed listener in Java Ask Question. Asked 12 years, 11 months ago. Active 12 months ago. Viewed k times. Just a note. EventObject Returns the object that fired the event. Examples that Use Change Listeners The following table lists the examples that use change listeners.

The change listener ignores the change events until the user releases the slider. Uses a change listener on a date-field spinner to change the color of the text as the spinner's date changes. Uses a change listener on a spinner to cycle through the gray scale as the spinner's value changes.

Both models explicitly fire change events when necessary.