Q:

Drawing outside a window in Java?

Is it possible to simply paint() (or use some other function) to the screen in Java?  As in draw over everything else on some coordinates of the screen itself, not inside some window.
If not, is it possible to make an invisible window that takes up the entire screen and use its glass pane to do it?  Would complications arise from doing this?  (Such as not being able to click on other applications)
Are there any other ways?
Thanks.
Edit:  I'm not trying to do full screen with this, by the way.

A:

In theory, you can create an transparent undecorated maximized JFrame. This will allow you to "paint" over the desktop. Problems are obvious: if an application stays behind this window, it will not receive any mouse events.
Months ago, I made an evil cheat to draw directly on Windows Explorer's Desktop: mixing some .NET coding with JNI and Sun's internal classes - that's surreal, but works.

