## Détails techniques

La classe `BackgroundTasks` provient directement de <a href="https://www.starlette.dev/background/" class="external-link" target="_blank">`starlette.background`</a>.

///

`status_code` 参数接收表示 HTTP 状态码的数字。

/// info | 说明

`status_code` 还能接收 `IntEnum` 类型，比如 Python 的 <a href="https://docs.python.org/3/library/http.html#http.HTTPStatus" class="external-link" target="_blank">`http.HTTPStatus`</a>。

///

它可以：

* 在响应中返回状态码
* 在 OpenAPI 概图（及用户界面）中存档：

<img src="/img/tutorial/response-status-code/image01.png">

/// note | 笔记

某些响应状态码表示响应没有响应体（参阅下一章）。

/// info | Информация

Вы можете прочитать больше про обработчики `lifespan` в Starlette в <a href="https://www.starlette.dev/lifespan/" class="external-link" target="_blank">документации Starlette по Lifespan</a>.

    @Override
    public void notifyFieldChangeUsingSetter(String fieldName, Object value, Object target) {
        if (logger.isDebugEnabled()) {
            logger.debug("  (s) " + fieldName + " = " + toString(value));
        }
    }

    @Override
    public void notifyFieldChangeUsingReflection(String fieldName, Object value, Object target) {
        if (logger.isDebugEnabled()) {

# FastAPI Cloud { #fastapi-cloud }

Você pode implantar sua aplicação FastAPI no <a href="https://fastapicloud.com" class="external-link" target="_blank">FastAPI Cloud</a> com um **único comando**; entre na lista de espera, caso ainda não tenha feito isso. 🚀

## Login { #login }

Certifique-se de que você já tem uma conta no **FastAPI Cloud** (nós convidamos você a partir da lista de espera 😉).

Depois, faça login:

<div class="termy">

```console

            return "Unknown";
        }
        Throwable target = t;
        if (target.getCause() == null) {
            return target.getClass().getSimpleName() + "[" + target.getMessage() + "]";
        }
        final StringBuilder sb = new StringBuilder();
        while (target != null) {
            sb.append(target.getClass().getSimpleName());
            if (target.getMessage() != null) {
                sb.append("[");

特別是，你可以直接使用 <a href="https://anyio.readthedocs.io/en/stable/" class="external-link" target="_blank">AnyIO</a> 來處理更複雜的並行使用案例，這些案例需要你在自己的程式碼中使用更高階的模式。

    private static Object getField(Object target, String name) {
        try {
            var f = target.getClass().getDeclaredField(name);
            f.setAccessible(true);
            return f.get(target);
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }

    private static void setField(Object target, String name, Object value) {
        try {

            // Given
            String prefix = "PREFIX";
            String target = "TARGET";
            String combined = prefix + target;
            byte[] combinedBytes = combined.getBytes(StandardCharsets.UTF_16LE);
            int prefixBytes = prefix.getBytes(StandardCharsets.UTF_16LE).length;
            int targetBytes = target.getBytes(StandardCharsets.UTF_16LE).length;

            // When

/target/
/.settings/
.project
.classpath
*.iml
.idea
.DS_Store
.repository
/.vscode