* the discussion in the {@link #addListener} documentation. All its warnings about heavyweight
   * listeners are also applicable to heavyweight callbacks passed to this method.
   *
   * <p>For a more general interface to attach a completion listener, see {@link #addListener}.
   *
   * <p>This method is similar to {@link java.util.concurrent.CompletableFuture#whenComplete} and

     * [Request.tag]. Use null to remove any existing tag assigned for [T].
     *
     * Use this API to attach timing, debugging, or other application data to a request so that
     * you may read it in interceptors, event listeners, or callbacks.
     */
    @JvmName("reifiedTag")
    inline fun <reified T : Any> tag(tag: T?): Builder = tag(T::class, tag)

    /**

     * caught above) can linger and affect listeners.
     */
  }

  /**
   * Called before runInterruptibly - if true, runInterruptibly and afterRanInterruptibly will not
   * be called.
   */
  abstract boolean isDone();

  /**
   * Do interruptible work here - do not complete Futures here, as their listeners could be
   * interrupted.
   */
  @ParametricNullness

        AbstractFutureState<?> future, @Nullable Listener expect, Listener update) {
      return UNSAFE.compareAndSwapObject(future, LISTENERS_OFFSET, expect, update);
    }

    @Override
    @Nullable Listener gasListeners(AbstractFutureState<?> future, Listener update) {
      while (true) {
        Listener listener = future.listenersField;
        if (update == listener) {
          return listener;
        }

    }

    @Override
    boolean casListeners(
        AbstractFutureState<?> future, @Nullable Listener expect, Listener update) {
      return listenersUpdater.compareAndSet(future, expect, update);
    }

    @Override
    @Nullable Listener gasListeners(AbstractFutureState<?> future, Listener update) {
      return (Listener) listenersUpdater.getAndSet(future, update);
    }

    @Override

  }

  @Override
  public final State state() {
    return delegate.state();
  }

  /**
   * @since 13.0
   */
  @Override
  public final void addListener(Listener listener, Executor executor) {
    delegate.addListener(listener, executor);
  }

  /**
   * @since 14.0
   */
  @Override
  public final Throwable failureCause() {
    return delegate.failureCause();
  }

  /**

  }

  @Override
  public final State state() {
    return delegate.state();
  }

  /**
   * @since 13.0
   */
  @Override
  public final void addListener(Listener listener, Executor executor) {
    delegate.addListener(listener, executor);
  }

  /**
   * @since 14.0
   */
  @Override
  public final Throwable failureCause() {
    return delegate.failureCause();
  }

  /**

        return buf.toString();
    }

    /**
     * Adds a listener for configuration updates.
     *
     * @param name     The name of the listener.
     * @param listener The listener to add.
     */
    public void addUpdateConfigListener(final String name, final Supplier<String> listener) {
        updateConfigListenerMap.put(name, listener);
    }

    /**
     * Checks if the cluster state has changed.

  // operation in the constructor.
  //
  // 1. In the listener that performs the callback. In this case it is fine since inputFuture is
  //    assigned prior to calling addListener, and addListener happens-before any invocation of the
  //    listener. Notably, this means that 'volatile' is unnecessary to make 'inputFuture' visible
  //    to the listener.
  //

        // Add second listener (should replace first)
        TestShutdownListener listener2 = new TestShutdownListener();
        scriptExecutor.addShutdownListener(listener2);

        // Call shutdown
        scriptExecutor.shutdown();

        // Verify only second listener was called
        assertFalse(listener1.wasShutdownCalled());
        assertTrue(listener2.wasShutdownCalled());