assertEquals(listener, jobExecutor.shutdownListener);

        // Verify listener is called on shutdown
        jobExecutor.shutdown();
        assertTrue(shutdownCalled.get());
    }

    public void test_addShutdownListener_replace() {
        // Test replacing shutdown listener
        AtomicInteger callCount = new AtomicInteger(0);
        ShutdownListener listener1 = new ShutdownListener() {

    /**
     * Initiates shutdown of the job executor.
     * This method notifies the shutdown listener to perform cleanup operations.
     */
    public void shutdown() {
        shutdownListener.onShutdown();
    }

    /**
     * Adds a shutdown listener to be notified when the executor is shutting down.
     *
     * @param listener the shutdown listener to add
     */

  /** Lock used whenever accessing the state variables (runningTasks, shutdown) of the executor */
  private final Object lock = new Object();

  /*
   * Conceptually, these two variables describe the executor being in
   * one of three states:
   *   - Active: shutdown == false
   *   - Shutdown: runningTasks > 0 and shutdown == true
   *   - Terminated: runningTasks == 0 and shutdown == true
   */
  @GuardedBy("lock")

    private volatile boolean shutdown;

    @Override
    public void shutdown() {
      shutdown = true;
    }

    @Override
    public List<Runnable> shutdownNow() {
      shutdown();
      return ImmutableList.of();
    }

    @Override
    public boolean isShutdown() {
      return shutdown;
    }

    @Override
    public boolean isTerminated() {

  /** Lock used whenever accessing the state variables (runningTasks, shutdown) of the executor */
  private final Object lock = new Object();

  /*
   * Conceptually, these two variables describe the executor being in
   * one of three states:
   *   - Active: shutdown == false
   *   - Shutdown: runningTasks > 0 and shutdown == true
   *   - Terminated: runningTasks == 0 and shutdown == true
   */
  @GuardedBy("lock")

    task: Task,
    delayNanos: Long = 0L,
  ) {
    taskRunner.withLock {
      if (shutdown) {
        if (task.cancelable) {
          taskRunner.logger.taskLog(task, this) { "schedule canceled (queue is shutdown)" }
          return
        }
        taskRunner.logger.taskLog(task, this) { "schedule failed (queue is shutdown)" }
        throw RejectedExecutionException()
      }

              while (!shutdown.get()) {
                interruptee.interrupt();
                Thread.yield();
              }
            }
          });
      this.shutdown = shutdown;
      start();
    }

    @SuppressWarnings("ThreadPriorityCheck") // TODO: b/175898629 - Consider onSpinWait.
    void shutdown() {
      shutdown.set(true);
      while (this.isAlive()) {
        Thread.yield();

    private volatile boolean shutdown;

    @Override
    public void shutdown() {
      shutdown = true;
    }

    @Override
    public List<Runnable> shutdownNow() {
      shutdown();
      return ImmutableList.of();
    }

    @Override
    public boolean isShutdown() {
      return shutdown;
    }

    @Override
    public boolean isTerminated() {

        return
      }
    }
    throw AssertionError("No such job: $url")
  }

  override fun shutdown() {
    shutdown = true
  }

  override fun shutdownNow(): List<Runnable> = throw UnsupportedOperationException()

  override fun isShutdown(): Boolean = shutdown

  override fun isTerminated(): Boolean = throw UnsupportedOperationException()

  override fun awaitTermination(

                  // which case we should skip right down to shutdown.
                  if (isRunning()) {
                    try {
                      AbstractExecutionThreadService.this.run();
                    } catch (Throwable t) {
                      restoreInterruptIfIsInterruptedException(t);
                      try {
                        shutDown();
                      } catch (Exception ignored) {