}

    /**
     * Add a listener for circuit breaker events
     *
     * @param listener the listener to add
     */
    public void addListener(CircuitBreakerListener listener) {
        if (listener != null) {
            listeners.add(listener);
        }
    }

    /**
     * Remove a listener
     *
     * @param listener the listener to remove
     */

        // 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());

        // Test with listener1
        factory.setOnDestroyListener(listener1);
        assertEquals(listener1, factory.getOnDestroyListener());
        factory.destroyObject(pooledObject);
        assertEquals(1, events.size());
        assertEquals("listener1", events.get(0));

        // Switch to listener2
        factory.setOnDestroyListener(listener2);
        assertEquals(listener2, factory.getOnDestroyListener());

  private static final ListenerCallQueue.Event<Listener> STARTING_EVENT =
      new ListenerCallQueue.Event<Listener>() {
        @Override
        public void call(Listener listener) {
          listener.starting();
        }

        @Override
        public String toString() {
          return "starting()";
        }
      };
  private static final ListenerCallQueue.Event<Listener> RUNNING_EVENT =

  private static final ListenerCallQueue.Event<Listener> STARTING_EVENT =
      new ListenerCallQueue.Event<Listener>() {
        @Override
        public void call(Listener listener) {
          listener.starting();
        }

        @Override
        public String toString() {
          return "starting()";
        }
      };
  private static final ListenerCallQueue.Event<Listener> RUNNING_EVENT =

    void enqueueStoppedEvent() {
      listeners.enqueue(STOPPED_EVENT);
    }

    void enqueueHealthyEvent() {
      listeners.enqueue(HEALTHY_EVENT);
    }

    void enqueueFailedEvent(Service service) {
      listeners.enqueue(
          new ListenerCallQueue.Event<Listener>() {
            @Override
            public void call(Listener listener) {
              listener.failure(service);
            }

   * <p>RuntimeExceptions thrown by a listener will be caught and logged. Any exception thrown
   * during {@code Executor.execute} (e.g., a {@code RejectedExecutionException}) will be caught and
   * logged.
   *
   * @param listener the listener to run when the service changes state is complete
   * @param executor the executor in which the listeners callback methods will be run. For fast,

        this.address = address;
    }

    /**
     * Adds a listener for connection events.
     *
     * @param listener The listener to add.
     */
    public void addOnConnectListener(final OnConnectListener listener) {
        onConnectListenerList.add(listener);
    }

    /**
     * Checks if the client is connected to OpenSearch.
     *

        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