Creating a JFrame you can click through

I'm trying to create a jframe that the user can click through. I'm not looking for opacity but transparency.

I need a solution that works on all OS and not just Windows because I can't use

WindowUtils.setWindowTransparent(frame, true);
WindowUtils.setWindowAlpha(frame, 0.6f);

or

AWTUtilities.setWindowOpaque(this, false);
AWTUtilities.setWindowOpacity(this, 0.8f);

Can I accomplish this with java alone? It's ok if there is a library that I must use.

EDIT: I have my jframe undecorated and here is the code for it.

frame = new JDialog();
frame.setUndecorated(true);
frame.setVisible(true);
frame.setOpacity(Shared.opacity);
frame.setLocation(0, 0);
frame.setSize(Shared.screenWidth, Shared.screenHeight);

When I say the user can click through what I mean is that if my frame is on top but they have a window under mine, clicking on mine would bring the one under on top.