import java.lang.annotation.Target;

/**
 * The annotated element must not be null.
 * <p>
 * Annotated fields must not be null after construction has completed.
 * <p>
 * When this annotation is applied to a method it applies to the method return value.
 *
 * @see Nullable
 * @since 4.0.0
 */
@Experimental
@Documented
@Retention(RetentionPolicy.CLASS)

## さらなる機能

[チュートリアル - ユーザーガイド](../tutorial/index.md){.internal-link target=_blank}により、**FastAPI**の主要な機能は十分に理解できたことでしょう。

以降のセクションでは、チュートリアルでは説明しきれなかったオプションや設定、および機能について説明します。

/// tip | "豆知識"

以降のセクションは、 **必ずしも"応用編"ではありません**。

ユースケースによっては、その中から解決策を見つけられるかもしれません。

///

## 先にチュートリアルを読む

[チュートリアル - ユーザーガイド](../tutorial/index.md){.internal-link target=_blank}の知識があれば、**FastAPI**の主要な機能を利用することができます。

## Technische Details

Die Klasse `BackgroundTasks` stammt direkt von <a href="https://www.starlette.io/background/" class="external-link" target="_blank">`starlette.background`</a>.

   * Returns a Writer that sends all output to the given {@link Appendable} target. Closing the
   * writer will close the target if it is {@link Closeable}, and flushing the writer will flush the
   * target if it is {@link java.io.Flushable}.
   *
   * @param target the object to which output will be sent
   * @return a new Writer object, unless target is a Writer, in which case the target is returned
   */

На всех предыдущих скриншотах используется <a href="https://code.visualstudio.com" class="external-link" target="_blank">Visual Studio Code</a>.

Но у вас будет такая же поддержка и с <a href="https://www.jetbrains.com/pycharm/" class="external-link" target="_blank">PyCharm</a>, и вообще с любым редактором Python:

<img src="/img/tutorial/body/image05.png">

/// tip | "Подсказка"

        # o tableTargetList: (NotRequired - Default list:{})
        #  If you want to include some tables in generating target expressly,
        #  you should specify the list of target table hints.
        #    e.g. list:{PURCHASE ; contain:MEMBER}
        #  This is only for the main schema. Additional schemas are unconcerned.

        }

        @Override
        public Activation transformActivation(Activation target) {
            stk.push(new ActivationFrame("activation", Optional.of(target)));
            try {
                return super.transformActivation(target);
            } finally {
                stk.pop();
            }
        }

        @Override

![Swagger UI interaction](https://fastapi.tiangolo.com/img/index/index-03-swagger-02.png)

* مستندات API جایگزین با <a href="https://github.com/Rebilly/ReDoc" class="external-link" target="_blank"><strong>ReDoc</strong></a>.

			<a class="nav-link active" href="${eolLink}" target="_olh"><em class="fas fa-times-circle text-danger"></a></li>
		</c:if>
		<c:if test="${developmentMode}">
			<li class="nav-item" data-toggle="tooltip" data-placement="left"
				title="<la:message key="labels.development_mode_warning" />">
				<a class="nav-link active" href="${installationLink}" target="_olh"><em class="fa fa-exclamation-triangle text-warning"></a></li>

# Build for both JAX and TF usage.  We do these in one place because they share
# almost all of the same cache layers
export DOCKER_BUILDKIT=1
for target in jax tf; do
  AR_IMAGE="$AR_IMAGE_PATH:$target-$TAG"
  docker pull "$AR_IMAGE" || true
  # Due to some flakiness of resources pulled in the build, allow the docker
  # command to reattempt build a few times in the case of failure (b/302558736)