public void testMustNotBeAbleToShutdown() {
   final AppScheduledExecutorService service = new AppScheduledExecutorService(getName());
   try {
     service.shutdown();
     fail();
   } catch (Exception ignored) {
   }
   try {
     service.shutdownNow();
     fail();
   } catch (Exception ignored) {
   } finally {
     service.shutdownAppScheduledExecutorService();
   }
 }