* the application is complete. It does so by using daemon threads and adding a shutdown hook to
   * wait for their completion.
   *
   * <p>This is mainly for fixed thread pools. See {@link Executors#newScheduledThreadPool(int)}.
   *
   * @param executor the executor to modify to make sure it exits when the application is finished
   * @param terminationTimeout how long to wait for the executor to finish before terminating the

   * the application is complete. It does so by using daemon threads and adding a shutdown hook to
   * wait for their completion.
   *
   * <p>This is mainly for fixed thread pools. See {@link Executors#newScheduledThreadPool(int)}.
   *
   * @param executor the executor to modify to make sure it exits when the application is finished
   * @param terminationTimeout how long to wait for the executor to finish before terminating the

    }

    static TestCondition createAndSignalAfter(long delay, TimeUnit unit) {
      final TestCondition testCondition = create();

      ScheduledExecutorService scheduledPool = Executors.newScheduledThreadPool(1);
      // If signal() fails somehow, we should see a failed test, even without looking at the Future.
      Future<?> unused =
          scheduledPool.schedule(
              new Runnable() {