java - new JFrame over a Fullscreen Application -

i'm testing java application in fullscreen mode, fullscreen works fine, when user presses button want display new jframe in middle of fullscreen (it has jframe, not jdialog) , call it:

public void actionperformed(actionevent ev) {     object source = ev.getsource();      if (source == refresh) {         // refresh     } else {         if (source == plan) {             //plan             final jframe dialog = new jmodificaciones();             dialog.pack();             dialog.setvisible(true);         } else {             // exit button             device.setdisplaymode(originaldm);             system.exit(0);         }     } } 

however makes fullscren application out of view , new jframe application background (for example mozilla), , want jframe appear on top of fullscreen application.

you can use external jframe fullscreen property , inside of can put jinternalframes center allignment don't need use jdialog