Question

Hi I was wondering if there is a way to set a jbutton to do the equivalent of setdefaultcloseoperation(JFrame.DISPOSE_ON_CLOSE) because I dont understand how a frame object is eligible for collection if it still has listeners when the frame is set invisible. I can send code if this doesn’t make sense.

Answer 1

• Top Level Containers (JFrame, JDialog …) miss implemetations for finalize(), then they are never GC’d

• equivalent for JFrame.DISPOSE_ON_CLOSE is only setVisible(false)

• you can returns all Top Level Containers from method Window[] wins = Window.getWindows();

• you can remove only all JComponents from ContentPane, for return used memory back

EDIT

• only visible container with Focus can listening or firing events from Swing Listeners