Use Toolkit.getDefaultToolkit().getScreenSize() to get the screen size, getSize() to get the frame size, and setLocation() to move the screen to the desired location.
It turns out that the setLocationRelativeTo() is a new addition to java.awt.Window (and consequently to JFrame) in JDK 1.4. This addition actually makes perfect sense, and I think that up to 1.4, that method implementation was simply in the wrong place (JDialog instead of its immediate parent) and that's why it didn't work for JFrame. Eugene.
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