PropertyChange Listener for icons.

I am trying to write a PropertyChange Listener which detects whether a JButton has an ImageIcon or not.

`"icon"` is a beans property but I can't seem to add iconListener or something equivalent to the PropertyChangeListener.

buttonArray[a].addChangeListener("icon",new iconListener()); // doesn't work

buttonArray[a].addChangeListener("icon", new ImageIconListener()); // doesn't work

Any guidance in the right direction is />