public void resetMenuBar() {
   mainMenu = new MainMenu(this);
   if (mainMenu.getComponentCount() > 0) {
     setJMenuBar(mainMenu);
     mainMenu.commit();
   } else {
     setJMenuBar(null);
     if (isVisible())
       setVisible(
           true); // work around for paint problem. see
                  // http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=4949810
   }
 }