Windows taskbar height/width

I can't figure out how to get the windows taskbar height dynamicaly to set my application fullscreen.
As you know, taskbar can be in four positions: bottom, top, left or right, so I'm wondering if it's possible to also know the current position to set the window bounds.

EDIT: Using Lukas link I tryied this:

GraphicsDevice myDevice;
Window myWindow;

try {
    myDevice.setFullScreenWindow(myWindow);
    ...
} finally {
    myDevice.setFullScreenWindow(null);
}

But I'm gettin a NullPointerException