Turn Java App into Screensaver

Question

Hello folks, for my study I wrote a program that solves mazes with depth-first search. Works perfecftly fine. I was wondering, how can I turn this Java-Program into a Screensaver application? Is there a way that windows starts my app when the screensaver would normally be activated?

Or is there another simple way to realise a java application as a screensaver (under windows, windows 7 would be the targeted OS Verison)

Answer 1

Windows screensavers are just exe files that accept certain command-line arguments, detailed here.

If you can compile your java app into an exe (I don't use java much any more so I'm not sure what tools exist), then rename it to .scr, that would do it. Or it might be enough just to make a .bat file like:

@echo off
java myProg.class %1

.. And rename it to .scr.

Answer 2

I have never used this but it might be the place to start. Screen Saver API.

Answer 3

I would look into the SaverBeans API for creating screen savers in Java.

Answer 4

A Windows screen saver is just program that accepts certain command line arguments. So in order to have your program be runnable as a screen saver you must code it to accept those arguments.

Next you will probably want your screen saver to run in full screen mode. This is very simple to do in Java as the example below shows:

 public final class ScreenSaver {

     public static final void main(final String[] args) throws Exception {
         UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());

         final JFrame screenSaverFrame = new JFrame();
         screenSaverFrame.setDefaultCloseOperation(
             WindowConstants.EXIT_ON_CLOSE);
         screenSaverFrame.setUndecorated(true);
         screenSaverFrame.setResizable(false);
         screenSaverFrame.add(new JLabel("This is a Java Screensaver!",
                              SwingConstants.CENTER), BorderLayout.CENTER);
         screenSaverFrame.validate();
         GraphicsEnvironment.getLocalGraphicsEnvironment()
                   .getDefaultScreenDevice()
                   .setFullScreenWindow(screenSaverFrame);
    }
}

Finally you will need to make your Java program into a Windows executable using something like Launch4j and give it .scr extension.