List<Future<?>> results = new ArrayList<>();
    Runnable[] manualExecutorTask = new Runnable[1];
    Executor manualExecutor =
        new Executor() {
          @Override
          public void execute(Runnable task) {
            manualExecutorTask[0] = task;
          }
        };

    results.add(serializer.submit(Callables.returning(null), manualExecutor));

  private final Method method;

  /** Executor to use for dispatching events to this subscriber. */
  private final Executor executor;

  private Subscriber(EventBus bus, Object target, Method method) {
    this.bus = bus;
    this.target = checkNotNull(target);
    this.method = method;
    method.setAccessible(true);

    this.executor = bus.executor();
  }

  }

  /**
   * Adds a listener that will be called using the given executor when events are later {@link
   * #enqueue enqueued} and {@link #dispatch dispatched}.
   */
  public void addListener(L listener, Executor executor) {
    checkNotNull(listener, "listener");
    checkNotNull(executor, "executor");
    listeners.add(new PerListenerQueue<>(listener, executor));
  }

  /**

import java.util.concurrent.ExecutionException;
import java.util.concurrent.Executor;
import java.util.concurrent.ExecutorService;
import org.jspecify.annotations.NullUnmarked;

/**
 * Tests for {@link ClosingFuture} that exercise {@link
 * ClosingFuture#finishToValueAndCloser(ValueAndCloserConsumer, Executor)}.
 */
@NullUnmarked

    assertThat(loadCount.get()).isEqualTo(1);
    assertThat(reloadCount.get()).isEqualTo(1);
    assertThat(loadAllCount.get()).isEqualTo(1);

    QueuingExecutor executor = new QueuingExecutor();
    CacheLoader<Object, Object> asyncReloader = CacheLoader.asyncReloading(baseLoader, executor);

    Object unused3 = asyncReloader.load(new Object());
    @SuppressWarnings("unused") // https://errorprone.info/bugpattern/FutureReturnValueIgnored

        ).respond(response().withBody("Peter the person!"))

      val results =
        (1..20).map {
          executor.submit {
            val response =
              client.newCall(Request((mockServer.secureEndpoint + "/person?name=peter").toHttpUrl())).execute()

            val body = response.body.string()
            assertThat(body).contains("Peter the person")
          }
        }

   * @param executor the executor in which the listeners callback methods will be run. For fast,
   *     lightweight listeners that would be safe to execute in any thread, consider {@link
   *     MoreExecutors#directExecutor}.
   * @since 13.0
   */
  void addListener(Listener listener, Executor executor);

  /**
   * The lifecycle states of a service.
   *

        }
      }
    }
  }

  /**
   * Checks if the executor has been shut down and increments the running task count.
   *
   * @throws RejectedExecutionException if the executor has been previously shutdown
   */
  private void startTask() {
    synchronized (lock) {
      if (shutdown) {
        throw new RejectedExecutionException("Executor already shutdown");
      }
      runningTasks++;
    }
  }

          public String get(long time, TimeUnit unit) {
            throw new CancellationException(); // BAD!!
          }

          @Override
          public void addListener(Runnable runnable, Executor executor) {
            executor.execute(runnable);
          }
        };
    future.setFuture(badFuture);
    ExecutionException expected = getExpectingExecutionException(future);

  }

  public void testTimeout() throws Exception {
    // Create a service whose executor will never run its commands
    Service service =
        new TestService() {
          @Override
          protected Executor executor() {
            return new Executor() {
              @Override
              public void execute(Runnable command) {}
            };
          }

          @Override