ExecutorService executor = newDirectExecutorService();
    executor.shutdown();
    assertThrows(RejectedExecutionException.class, () -> executor.execute(() -> {}));
  }

  public <T> void testListeningExecutorServiceInvokeAllJavadocCodeCompiles() throws Exception {
    ListeningExecutorService executor = newDirectExecutorService();
    List<Callable<T>> tasks = ImmutableList.of();
    List<? extends Future<?>> unused = executor.invokeAll(tasks);