final TestCloseable closeable2 = new TestCloseable("closeable2");
  final TestCloseable closeable3 = new TestCloseable("closeable3");
  final TestCloseable closeable4 = new TestCloseable("closeable4");

  final Waiter waiter = new Waiter();
  final CountDownLatch futureCancelled = new CountDownLatch(1);
  final Exception exception = new Exception();
  final Closeable mockCloseable = Mockito.mock(Closeable.class);

  @Override

  final TestCloseable closeable2 = new TestCloseable("closeable2");
  final TestCloseable closeable3 = new TestCloseable("closeable3");
  final TestCloseable closeable4 = new TestCloseable("closeable4");

  final Waiter waiter = new Waiter();
  final CountDownLatch futureCancelled = new CountDownLatch(1);
  final Exception exception = new Exception();
  final Closeable mockCloseable = Mockito.mock(Closeable.class);

  @Override

    }

    /** Performs a GAS operation on the {@link #waiters} field. */
    @Override
    Waiter gasWaiters(AbstractFuture<?> future, Waiter update) {
      while (true) {
        Waiter waiter = future.waiters;
        if (update == waiter) {
          return waiter;
        }
        if (casWaiters(future, waiter, update)) {
          return waiter;
        }
      }
    }

    if (waiter.isAlive()) {
      waiter.interrupt();
      fail("awaitTermination failed to trigger after shutdown()");
    }
  }

  /** Wait for the given thread to reach the {@link State#TIMED_WAITING} thread state. */
  void awaitTimedWaiting(Thread thread) {
    while (true) {
      switch (thread.getState()) {
        case BLOCKED:
        case NEW:
        case RUNNABLE:

    if (waiter.isAlive()) {
      waiter.interrupt();
      fail("awaitTermination failed to trigger after shutdown()");
    }
  }

  /** Wait for the given thread to reach the {@link State#TIMED_WAITING} thread state. */
  void awaitTimedWaiting(Thread thread) {
    while (true) {
      switch (thread.getState()) {
        case BLOCKED:
        case NEW:
        case RUNNABLE:

    final NoOpService service = new NoOpService();
    Thread waiter =
        new Thread() {
          @Override
          public void run() {
            service.awaitTerminated();
          }
        };
    waiter.start();
    service.startAsync().awaitRunning();
    assertEquals(State.RUNNING, service.state());
    service.stopAsync();

    // Check that we wait long enough anyway (presumably as long as MAX_VALUE nanos):
    TimedWaiterThread waiter = new TimedWaiterThread(future, Long.MAX_VALUE, SECONDS);
    waiter.start();
    waiter.awaitWaiting();

    future.set(1);
    waiter.join();
  }

  @J2ktIncompatible // TODO(b/324550390): Enable
  public void testSetNull() throws Exception {
    future.set(null);

    final NoOpService service = new NoOpService();
    Thread waiter =
        new Thread() {
          @Override
          public void run() {
            service.awaitTerminated();
          }
        };
    waiter.start();
    service.startAsync().awaitRunning();
    assertEquals(State.RUNNING, service.state());
    service.stopAsync();

    WaiterThread waiter1 = new WaiterThread(future);
    waiter1.start();
    waiter1.awaitWaiting();

    WaiterThread waiter2 = new WaiterThread(future);
    waiter2.start();
    waiter2.awaitWaiting();
    // The waiter queue should be waiter2->waiter1

    // This should wake up waiter1 and cause the waiter1 node to be removed.
    waiter1.interrupt();

    waiter1.join();

    // Check that we wait long enough anyway (presumably as long as MAX_VALUE nanos):
    TimedWaiterThread waiter = new TimedWaiterThread(future, Long.MAX_VALUE, SECONDS);
    waiter.start();
    waiter.awaitWaiting();

    future.set(1);
    waiter.join();
  }

  @J2ktIncompatible // TODO(b/324550390): Enable
  public void testSetNull() throws Exception {
    future.set(null);