val hpackWriter: Hpack.Writer = Hpack.Writer(out = hpackBuffer)

  @Throws(IOException::class)
  fun connectionPreface() {
    withLock {
      if (closed) throw IOException("closed")
      if (!client) return // Nothing to write; servers don't send connection headers!
      if (logger.isLoggable(FINE)) {
        logger.fine(format(">> CONNECTION ${CONNECTION_PREFACE.hex()}"))
      }
      sink.write(CONNECTION_PREFACE)
      sink.flush()

  /**
   * Start the service.
   *
   * <p>By default this method does nothing.
   */
  protected void startUp() throws Exception {}

  /**
   * Stop the service. This is guaranteed not to run concurrently with {@link #runOneIteration}.
   *
   * <p>By default this method does nothing.
   */
  protected void shutDown() throws Exception {}

  /**

  /**
   * Start the service.
   *
   * <p>By default this method does nothing.
   */
  protected void startUp() throws Exception {}

  /**
   * Stop the service. This is guaranteed not to run concurrently with {@link #runOneIteration}.
   *
   * <p>By default this method does nothing.
   */
  protected void shutDown() throws Exception {}

  /**

      by You to the Licensor shall be under the terms and conditions of
      this License, without any additional terms or conditions.
      Notwithstanding the above, nothing herein shall supersede or modify
      the terms of any separate license agreement you may have executed
      with Licensor regarding such Contributions.

      by You to the Licensor shall be under the terms and conditions of
      this License, without any additional terms or conditions.
      Notwithstanding the above, nothing herein shall supersede or modify
      the terms of any separate license agreement you may have executed
      with Licensor regarding such Contributions.

      by You to the Licensor shall be under the terms and conditions of
      this License, without any additional terms or conditions.
      Notwithstanding the above, nothing herein shall supersede or modify
      the terms of any separate license agreement you may have executed
      with Licensor regarding such Contributions.

        case STARTING:
        case STOPPING:
          snapshot = new StateSnapshot(FAILED, false, cause);
          enqueueFailedEvent(previous, cause);
          break;
        case FAILED:
          // Do nothing
          break;
      }
    } finally {
      monitor.leave();
      dispatchListenerEvents();
    }
  }

  @Override
  public final boolean isRunning() {
    return state() == RUNNING;

Contributor under this Agreement, whether expressly, by implication,
estoppel or otherwise. All rights in the Program not expressly granted
under this Agreement are reserved. Nothing in this Agreement is intended
to be enforceable by any entity that is not a Contributor or Recipient.
No third-party beneficiary rights are created under this Agreement.

Exhibit A - Form of Secondary Licenses Notice

			case freeVersionTask:
				oi := v.ObjectInfo
				traceFn := globalLifecycleSys.trace(oi)
				if !oi.TransitionedObject.FreeVersion {
					// nothing to be done
					continue
				}

				ignoreNotFoundErr := func(err error) error {
					switch {
					case isErrVersionNotFound(err), isErrObjectNotFound(err):
						return nil
					}
					return err

#### Kiểm tra `openapi.json`

Nếu bạn tò mò về việc cấu trúc OpenAPI nhìn như thế nào thì FastAPI tự động sinh một JSON (schema) với các mô tả cho tất cả API của bạn.