return true;
    }
    return false;
  }

  final @Nullable Object value() {
    return value;
  }

  final @Nullable Listener listeners() {
    return listeners;
  }

  final void releaseWaiters() {}

  AbstractFutureState() {}

  static final Object NULL = new Object();

  static final LazyLogger log = new LazyLogger(AbstractFuture.class);

  static final boolean GENERATE_CANCELLATION_CAUSES = false;

  final @Nullable Listener listeners() {
    return listenersField;
  }

  /** Releases all threads in the {@link #waitersField} list, and clears the list. */
  final void releaseWaiters() {
    Waiter head = gasWaiters(Waiter.TOMBSTONE);
    for (Waiter currentWaiter = head; currentWaiter != null; currentWaiter = currentWaiter.next) {
      currentWaiter.unpark();
    }
  }

  final @Nullable Listener listeners() {
    return listenersField;
  }

  /** Releases all threads in the {@link #waitersField} list, and clears the list. */
  final void releaseWaiters() {
    Waiter head = gasWaiters(Waiter.TOMBSTONE);
    for (Waiter currentWaiter = head; currentWaiter != null; currentWaiter = currentWaiter.next) {
      currentWaiter.unpark();
    }
  }