a) You can use a JMenuBar, which allows enabling/disabling the JMenuItems b) You could just remove the items that are not available from the JComboBox c) You could provide a custom renderer for the JComboBox items to grey them out (
How to Use Combo Boxes (The Java™ Tutorials > Creating a GUI With JFC/Swing > Using Swing Components) has a demo how you can add a custom renderer) - the items can still be selected and fire events, but from the users point of view (provided you don't react to the action) they wouldn't know the difference (see
Enable/Disable JComboBox Items ).