Are you planning to vary the size of the JFrame with the size of the user's screen?
In my limited experience, if I set the size of the JFrame, optimize my component layout for that size, and then set the JFrame to not change sizes, my layout stays OK. I've had minor problems with different screen resolutions, but those have been manageable. I've also noticed that others managing large frames that might grow initiate them at (0, 0) to have the maximum screen real estate available for growth.
These approaches may not suit your requirements, so please explain what you're trying to do.
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