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
     */

    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() {

    ExecutorService service = mock(ExecutorService.class);
    application.addDelayedShutdownHook(service, 2, SECONDS);
    verify(service, Mockito.never()).shutdown();
    application.shutdown();
    InOrder shutdownFirst = Mockito.inOrder(service);
    shutdownFirst.verify(service).shutdown();
    shutdownFirst.verify(service).awaitTermination(2, SECONDS);
  }

              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() {

    }

    public void test_shutdown_withListener() {
        // Add shutdown listener
        TestShutdownListener listener = new TestShutdownListener();
        scriptExecutor.addShutdownListener(listener);

        // Verify listener not called yet
        assertFalse(listener.wasShutdownCalled());

        // Call shutdown
        scriptExecutor.shutdown();

        // Verify listener was called

여러 개의 이벤트 핸들러 함수를 추가할 수 있습니다.

애플리케이션은 모든 `startup` 이벤트 핸들러가 완료될 때까지 요청을 받기 시작하지 않습니다.

### `shutdown` 이벤트

애플리케이션이 종료될 때 실행되어야 하는 함수를 추가하려면, `"shutdown"` 이벤트로 선언합니다:

{* ../../docs_src/events/tutorial002.py hl[6] *}

여기서, `shutdown` 이벤트 핸들러 함수는 `"Application shutdown"`이라는 텍스트를 `log.txt` 파일에 기록합니다.

/// info | 정보

`open()` 함수에서 `mode="a"`는 "추가"를 의미하므로, 파일에 있는 기존 내용은 덮어쓰지 않고 새로운 줄이 추가됩니다.

              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();

### `shutdown` event { #shutdown-event }

To add a function that should be run when the application is shutting down, declare it with the event `"shutdown"`:

{* ../../docs_src/events/tutorial002.py hl[6] *}

Here, the `shutdown` event handler function will write a text line `"Application shutdown"` to a file `log.txt`.

/// info