/** Updates the UIs of all the known Frames. */
 private static void updateAllUIs() {
   // Check if the current UI is WindowsLookAndfeel and flush the XP style map.
   // Note: Change the package test if this class is moved to a different package.
   Class uiClass = UIManager.getLookAndFeel().getClass();
   if (uiClass.getPackage().equals(DesktopProperty.class.getPackage())) {
     XPStyle.invalidateStyle();
   }
   Frame appFrames[] = Frame.getFrames();
   for (int j = 0; j < appFrames.length; j++) {
     updateWindowUI(appFrames[j]);
   }
 }
 private static URL packageRelativeResource(String resourceName, Class<?> clazz) {
   String directoryPrefix = '/' + clazz.getPackage().getName().replaceAll("\\.", "/") + '/';
   return clazz.getResource(directoryPrefix + resourceName);
 }