private static Constructor<?> getXWindowAttributesCtor() throws Exception {
      if (ctor == null) {
        var clazz = Class.forName("sun.awt.X11.XWindowAttributes");
        ctor = clazz.getConstructor();
        get_map_state = method(clazz, "get_map_state");
        dispose = method(clazz, "dispose");
        getPData = method(clazz, "getPData");
      }

      return ctor;
    }
private static Constructor<?> getXWindowAttributesCtor()