处置一个JFrame

Question

I'm trying to dispose my JFrame with the following method:

private void killJFrame(JFrame jFrame) {
    SwingUtilities.invokeLater(() -> jFrame.dispose());
}

When killJFrame() is executed, the JFrame becomes invisible and it seems like it worked. However, when calling Frame.getFrames() , the returned array still contains all of the JFrame s which were created in my application.

There is no difference if I try it like this:

private void killJFrame(JFrame jFrame) {
     jFrame.dispose();
}

I just thought it would be better if I disposed my JFrame on the event dispatch thread.

Why does the returned array of Frame.getFrames() still contain my JFrames ?

Answer 1

Java uses a garbage collector. Disposing the frame only makes it ready for garbage collection, thus those JFrames exist until the GC comes in and deletes them.

JFrame.dispose() only frees up the resources .

In Java, objects are references pointing to a group of resources. So if the memory is cleared, the reference is still left over.