}

    @Override
    public final boolean isShutdown() {
      return delegate.isShutdown();
    }

    @Override
    public final boolean isTerminated() {
      return delegate.isTerminated();
    }

    @Override
    public final void shutdown() {
      delegate.shutdown();
    }

    @Override
    public final List<Runnable> shutdownNow() {

    }

    @Override
    public final boolean isShutdown() {
      return delegate.isShutdown();
    }

    @Override
    public final boolean isTerminated() {
      return delegate.isTerminated();
    }

    @Override
    public final void shutdown() {
      delegate.shutdown();
    }

    @Override
    public final List<Runnable> shutdownNow() {

    void execute(Runnable runnable) {
        threads.add(owner.startThread(runnable))
    }

    void shutdown() {
        throw new UnsupportedOperationException()
    }

    List<Runnable> shutdownNow() {
        throw new UnsupportedOperationException()
    }

    boolean isShutdown() {
        throw new UnsupportedOperationException()
    }

    boolean isTerminated() {

              }
            }
          });
      this.shutdown = shutdown;
      start();
    }

    void shutdown() {
      shutdown.set(true);
      while (this.isAlive()) {
        Thread.yield();
      }
    }
  }

  void assertWrapsInterruptedException(RuntimeException e) {
    assertThat(e).hasMessageThat().contains("Unexpected interrupt");

### `shutdown` event

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

```Python hl_lines="6"
{!../../../docs_src/events/tutorial002.py!}
```

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

!!! info

		t.Parallel()
		p := NewPushQueue()
		defer p.ShutDown()
		p.Enqueue(proxies[0], &model.PushRequest{})
		p.Enqueue(proxies[1], &model.PushRequest{})

		ExpectDequeue(t, p, proxies[0])
		ExpectDequeue(t, p, proxies[1])
	})

	t.Run("remove too many", func(t *testing.T) {
		t.Parallel()
		p := NewPushQueue()
		defer p.ShutDown()

		p.Enqueue(proxies[0], &model.PushRequest{})

	// ShutdownSendRetryAfter dictates when to initiate shutdown of the HTTP
	// Server during the graceful termination of the apiserver. If true, we wait
	// for non longrunning requests in flight to be drained and then initiate a
	// shutdown of the HTTP Server. If false, we initiate a shutdown of the HTTP
	// Server as soon as ShutdownDelayDuration has elapsed.

# Routes
# Home page
GET     /                           controllers.Application.index

GET     /shutdown                   controllers.Application.shutdown

# Map static resources from the /public folder to the /assets URL path

本例中，`startup` 事件处理器函数为项目数据库（只是**字典**）提供了一些初始值。

**FastAPI** 支持多个事件处理器函数。

只有所有 `startup` 事件处理器运行完毕，**FastAPI** 应用才开始接收请求。

## `shutdown` 事件

使用 `shutdown` 事件声明 `app` 关闭时运行的函数：

```Python hl_lines="6"
{!../../../docs_src/events/tutorial002.py!}
```

此处，`shutdown` 事件处理器函数在 `log.txt` 中写入一行文本 `Application shutdown`。

!!! info "说明"

    `open()` 函数中，`mode="a"` 指的是**追加**。因此这行文本会添加在文件已有内容之后，不会覆盖之前的内容。

!!! tip "提示"

	natsserver "github.com/nats-io/nats-server/v2/test"
)

func TestNatsConnPlain(t *testing.T) {
	opts := natsserver.DefaultTestOptions
	opts.Port = 14222
	s := natsserver.RunServer(&opts)
	defer s.Shutdown()

	clientConfig := &NATSArgs{
		Enable: true,
		Address: xnet.Host{
			Name:      "localhost",
			Port:      (xnet.Port(opts.Port)),
			IsPortSet: true,
		},
		Subject: "test",
	}