return 0;
    }
  }

  @Override
  public ListenableScheduledFuture<?> scheduleAtFixedRate(
      Runnable command, long initialDelay, long period, TimeUnit unit) {
    throw new UnsupportedOperationException("scheduleAtFixedRate is not supported.");
  }

  @Override
  public ListenableScheduledFuture<?> scheduleWithFixedDelay(

      return NeverScheduledFuture.create();
    }

    @Override
    public ListenableScheduledFuture<?> scheduleAtFixedRate(
        Runnable command, long initialDelay, long period, TimeUnit unit) {
      return NeverScheduledFuture.create();
    }

    @Override
    public ListenableScheduledFuture<?> scheduleWithFixedDelay(

  }

  @Override
  public final ScheduledFuture<?> scheduleAtFixedRate(
      Runnable command, long initialDelay, long period, TimeUnit unit) {
    return delegate.scheduleAtFixedRate(wrapTask(command), initialDelay, period, unit);
  }

  @Override
  public final ScheduledFuture<?> scheduleWithFixedDelay(
      Runnable command, long initialDelay, long delay, TimeUnit unit) {

    @Override
    public ScheduledFuture<?> scheduleAtFixedRate(
        Runnable command, long initialDelay, long period, TimeUnit unit) {
      assertThat(command).isInstanceOf(WrappedRunnable.class);
      lastMethodCalled = "scheduleAtFixedRate";
      lastInitialDelay = initialDelay;
      lastDelay = period;
      lastUnit = unit;
      return null;
    }

    @Override

      return 0;
    }
  }

  @Override
  public ListenableScheduledFuture<?> scheduleAtFixedRate(
      Runnable command, long initialDelay, long period, TimeUnit unit) {
    throw new UnsupportedOperationException("scheduleAtFixedRate is not supported.");
  }

  @Override
  public ListenableScheduledFuture<?> scheduleWithFixedDelay(

  /** @since 15.0 (previously returned ScheduledFuture) */
  @Override
  ListenableScheduledFuture<?> scheduleAtFixedRate(
      Runnable command, long initialDelay, long period, TimeUnit unit);

  /** @since 15.0 (previously returned ScheduledFuture) */
  @Override
  ListenableScheduledFuture<?> scheduleWithFixedDelay(
      Runnable command, long initialDelay, long delay, TimeUnit unit);

2.  APIs without `@Beta` will remain binary-compatible for the indefinite
    future. (Previously, we sometimes removed such APIs after a deprecation
    period. The last release to remove non-`@Beta` APIs was Guava 21.0.) Even
    `@Deprecated` APIs will remain (again, unless they are `@Beta`). We have no
    plans to start removing things again, but officially, we're leaving our

    // this will happen once the interrupt has been set which means that
    // 1. the runner has been woken up
    // 2. the interrupter is stuck in the call the Thread.interrupt()

    // after some period of time the runner thread should become blocked on the task because it is
    // waiting for the slow interrupting thread to complete Thread.interrupt
    awaitBlockedOnInstanceOf(runner, InterruptibleTask.Blocker.class);

      return NeverScheduledFuture.create();
    }

    @Override
    public ListenableScheduledFuture<?> scheduleAtFixedRate(
        Runnable command, long initialDelay, long period, TimeUnit unit) {
      return NeverScheduledFuture.create();
    }

    @Override
    public ListenableScheduledFuture<?> scheduleWithFixedDelay(

    // this will happen once the interrupt has been set which means that
    // 1. the runner has been woken up
    // 2. the interrupter is stuck in the call the Thread.interrupt()

    // after some period of time the runner thread should become blocked on the task because it is
    // waiting for the slow interrupting thread to complete Thread.interrupt
    awaitBlockedOnInstanceOf(runner, InterruptibleTask.Blocker.class);