/** 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")

        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(

    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() {

### `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_py310.py hl[6] *}

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

/// info

    /**
     * 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() {

        assertEquals(listener, jobExecutor.shutdownListener);

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

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

		return srv.Serve(l)
	}

	return serve, err
}

// Shutdown - shuts down HTTP server.
func (srv *Server) Shutdown() error {
	srv.listenerMutex.Lock()
	if srv.listener == nil {
		srv.listenerMutex.Unlock()
		return http.ErrServerClosed
	}
	srv.listenerMutex.Unlock()

	if atomic.AddUint32(&srv.inShutdown, 1) > 1 {
		// shutdown in progress
		return http.ErrServerClosed
	}

   * message buffer (16 MiB) will be rejected and trigger a [graceful shutdown][close] of this web
   * socket. This method returns false in that case, and in any other case where this web socket is
   * closing, closed, or canceled.
   *
   * This method returns immediately.
   */
  fun send(bytes: ByteString): Boolean

  /**
   * Attempts to initiate a graceful shutdown of this web socket. Any already-enqueued messages will

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