wrote:

I don't see it at all.  Is there a specific way you're maximizing the
window?  Are you doing it programmatically (with setExtendedState) or
using the button on the title bar?

I've noticed this also, intermittent behaviour.
Often it will maximise as a native app for ~1 second then maximise again to
cover the task bar.  This was in 1.4.2 but also I see the same in 1.5

--
Mike W

I am guessing that you have done a setDefaultLookAndFeelDecorated( true );

If so, then the answer is [sort of] expected behavior.  Sun's position is
that this is "as designed".  I would call it a specification error.

The key point is that a maximized Frame occupies the client area of the
screen when it is decorated and occupies the full screen when it is
undecorated.  I am not sure I understand why that should be the case, but
that is how Sun says it should work.  I agree that there are cases where
you want undecorated frames to maximize to full screen (I just used this a
few weeks ago), but the programmer needs more control over this.

You have run into the case where the behavior is *clearly* wrong, at least
in my opinion.  When you set DefaultLookAndFeelDecorated to true, a JFrame
will ask the look-and-feel draw the frame decorations.  Assuming that the
look-and-feel supports this (Metal does, Windows does not), it sets the
Frame to undecorated and tells the look-and-feel to draw the decorations.
But since the Frame is undecorated (it does not know or care what the LAF
is drawing inside the Frame), it maximizes to full screen.

There is more information on the issue (including a work-around) at:

   http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4737788