protected void processMouseWheelEvent(MouseWheelEvent e) {
   MouseWheelEvent transformedEvent = (MouseWheelEvent) transformMouseEvent(e);
   MouseWheelListener[] mouseWheelListeners =
       transformedEvent.getComponent().getMouseWheelListeners();
   for (MouseWheelListener listener : mouseWheelListeners) {
     listener.mouseWheelMoved(transformedEvent);
   }
   super.processMouseWheelEvent(e);
 }