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

* Documentation d'API alternative avec [**ReDoc**](https://github.com/Rebilly/ReDoc).

![ReDoc](https://fastapi.tiangolo.com/img/index/index-06-redoc-02.png)

### Uniquement du Python moderne { #just-modern-python }

- **Documenter** le paramètre dans la *chemin d'accès* du schéma OpenAPI (il apparaîtra donc dans l’**interface de documentation automatique**)

## Alternative (ancienne) : `Query` comme valeur par défaut { #alternative-old-query-as-the-default-value }

![Swagger UI](https://fastapi.tiangolo.com/img/index/index-01-swagger-ui-simple.png)

### Альтернативная документация API { #alternative-api-docs }

Теперь откройте [http://127.0.0.1:8000/redoc](http://127.0.0.1:8000/redoc).

Вы увидите альтернативную автоматическую документацию (предоставлена [ReDoc](https://github.com/Rebilly/ReDoc)):

   * There is no need for a blocking lock; when the lock is not
   * available, threads try other slots (or the base).  During these
   * retries, there is increased contention and reduced locality,
   * which is still better than alternatives.
   *
   * Per-thread hash codes are initialized to random values.
   * Contention and/or table collisions are indicated by failed
   * CASes when performing an update operation (see method

在我們的範例中，並不是直接用它，而是把它傳給 FastAPI 來使用。

`FastAPI` 應用的 `lifespan` 參數需要一個**非同步內容管理器**，所以我們可以把剛寫好的 `lifespan` 非同步內容管理器傳給它。

{* ../../docs_src/events/tutorial003_py310.py hl[22] *}

## 替代事件（已棄用） { #alternative-events-deprecated }

/// warning

目前建議使用上面所述，透過 `FastAPI` 應用的 `lifespan` 參數來處理 *startup* 與 *shutdown*。如果你提供了 `lifespan` 參數，`startup` 與 `shutdown` 事件處理器將不會被呼叫。要嘛全用 `lifespan`，要嘛全用事件，不能同時混用。

你大概可以直接跳過這一節。

///

            c[ci++] = '|';
            NL.getChars(0, NL_LENGTH, c, ci);
            ci += NL_LENGTH;
        } while (si < length);

        ps.println(c);
    }

    /**
     * This is an alternative to the <code>java.lang.Integer.toHexString</code>
     * method. It is an efficient relative that also will pad the left side so
     * that the result is <code>size</code> digits.
     *

Other HTTP libraries exist that fill that gap allowing extensive customisation including potentially
invalid requests.

Example Limitations

* Does not allow GET with a body.
* Cache is not an interface with alternative implementations.

Get a URL
---------

This program downloads a URL and prints its contents as a string. [Full source][get_example].

```java
OkHttpClient client = new OkHttpClient();

 *
 * <ul>
 *   <li>The raw {@code long} values returned by {@code nanoTime} are meaningless and unsafe to use
 *       in any other way than how {@code Stopwatch} uses them.
 *   <li>An alternative source of nanosecond ticks can be substituted, for example for testing or
 *       performance reasons, without affecting most of your code.
 * </ul>
 *

  }

  /**
   * Indicates that the load and store operations will be very efficient because of use of VarHandle
   * or Unsafe. May be useful for calling code to fall back on an alternative implementation that is
   * slower than those implementations but faster than the pure-Java mask-and-shift.
   */
  static boolean usingFastPath() {
    return byteArray.usesFastPath();
  }

  /**

 *
 * // In case bug 12345 happens again we'd rather just die
 * Verify.verify(bill.status() == Status.UNPAID,
 *     "Unexpected bill status: %s", bill.status());
 * }
 *
 * <h3>Comparison to alternatives</h3>
 *
 * <p><b>Note:</b> In some cases the differences explained below can be subtle. When it's unclear
 * which approach to use, <b>don't worry</b> too much about it; just pick something that seems