// GWT's ConcurrentHashMap is a wrapper around HashMap, but it rejects null keys, which matches
    // the behaviour of the non-GWT implementation of newConcurrentHashSet().
    // On the other hand HashSet might be better for code size if apps aren't
    // already using Collections.newSetFromMap and ConcurrentHashMap.
    return Collections.newSetFromMap(new ConcurrentHashMap<E, Boolean>());
  }

## Future { #future }

By this point, it's already clear that **FastAPI** with its ideas is being useful for many people.

It is being chosen over previous alternatives for suiting many use cases better.

Many developers and teams already depend on **FastAPI** for their projects (including me and my team).

But still, there are many improvements and features to come.

**FastAPI** has a great future ahead.

# exec".
# Important: "tfrun foo | bar" is "( tfrun foo ) | bar", not "tfrun (foo | bar)".
# Therefore, "tfrun" commands cannot include pipes -- which is
# probably for the better. If a pipe is necessary for something, it is probably
# complex. Write a well-documented script under utilities/ to encapsulate the
# functionality instead.
tfrun() { "$@"; }

if [[ $(uname -s) = MSYS_NT* ]]; then

0.082 responseBodyStart
0.082 responseBodyEnd
0.083 connectionReleased
0.083 callEnd
```

Notice how no connect events are fired for the second call. It reused the connection from the first request for dramatically better performance.

### EventListener.Factory

eine relative URL verwenden, würde sich das, wenn sich Ihre API unter `https://example.com/` befindet, auf `https://example.com/token` beziehen. Wenn sich Ihre API jedoch unter `https://example.com/api/v1/` befände, würde es sich auf `https://example.com/api/v1/token` beziehen.

Die Verwendung einer relativen URL ist wichtig, um sicherzustellen, dass Ihre Anwendung auch in einem fortgeschrittenen Anwendungsfall, wie [hinter einem Proxy](../../advanced/behind-a-proxy.md){.internal-link target=_blank},...

Но в нашем случае одно и то же приложение **FastAPI** будет работать с API и аутентификацией.

Итак, рассмотрим его с этой упрощенной точки зрения:

* Пользователь вводит на фронтенде `имя пользователя` и `пароль` и нажимает `Enter`.
* Фронтенд (работающий в браузере пользователя) отправляет эти `имя пользователя` и `пароль` на определенный URL в нашем API (объявленный с помощью параметра `tokenUrl="token"`).

    assertEquals(c, navigableSet.higher(b));
    assertEquals(null, navigableSet.higher(c));
  }

  /*
   * TODO(cpovirk): make "too small" and "too large" elements available for better navigation
   * testing. At that point, we may be able to eliminate the "hole" tests, which would mean that
   * ContiguousSet's tests would no longer need to suppress them.
   */
  @CollectionSize.Require(SEVERAL)

   *
   * @throws IllegalArgumentException if the resource is not found
   */
  @CanIgnoreReturnValue // being used to check if a resource exists
  // TODO(cgdecker): maybe add a better way to check if a resource exists
  // e.g. Optional<URL> tryGetResource or boolean resourceExists
  public static URL getResource(String resourceName) {
    ClassLoader loader =
        MoreObjects.firstNonNull(

    /**
     * Clear all pending operations
     */
    public void clearPendingOperations() {
        pendingOperations.clear();
    }

    /**
     * Calculate channel score for load balancing (higher is better)
     *
     * @return channel score
     */
    public int getScore() {
        int score = 100;

        // Adjust based on state
        if (state == ChannelState.ACTIVE)

            * **FastAPI** adds a reference here to the global JSON Schemas in another place in your OpenAPI instead of including it directly. This way, other applications and clients can use those JSON Schemas directly, provide better code generation tools, etc.

///

The generated responses in the OpenAPI for this *path operation* will be:

```JSON hl_lines="3-12"
{
    "responses": {
        "404": {