Callable<@Nullable Void> callable =
        new Callable<@Nullable Void>() {
          @Override
          public @Nullable Void call() throws Exception {
            assertEquals(Thread.currentThread().getName(), newName.get());
            return null;
          }
        };
    Callables.threadRenaming(callable, newName).call();

    set: list,
    UUID: str,
    Url: str,
    AnyUrl: str,
}


def generate_encoders_by_class_tuples(
    type_encoder_map: dict[Any, Callable[[Any], Any]],
) -> dict[Callable[[Any], Any], tuple[Any, ...]]:
    encoders_by_class_tuples: dict[Callable[[Any], Any], tuple[Any, ...]] = defaultdict(
        tuple
    )
    for type_, encoder in type_encoder_map.items():

          }
        };

    results.add(serializer.submit(Callables.returning(null), manualExecutor));
    Future<?>[] thingToCancel = new Future<?>[1];
    results.add(
        serializer.submit(
            new Callable<@Nullable Void>() {
              @Override
              public @Nullable Void call() {
                thingToCancel[0].cancel(false);
                return null;

   * <p>Cancellation does not propagate from the output future to a callable that has begun to
   * execute, but if the output future is cancelled before {@link Callable#call()} is invoked,
   * {@link Callable#call()} will not be invoked.
   */
  public <T extends @Nullable Object> ListenableFuture<T> submit(
      Callable<T> callable, Executor executor) {
    checkNotNull(callable);
    checkNotNull(executor);
    return submitAsync(

import gzip
from typing import Annotated, Callable

from fastapi import Body, FastAPI, Request, Response
from fastapi.routing import APIRoute


class GzipRequest(Request):
    async def body(self) -> bytes:
        if not hasattr(self, "_body"):
            body = await super().body()
            if "gzip" in self.headers.getlist("Content-Encoding"):
                body = gzip.decompress(body)
            self._body = body

   * <p>Cancellation does not propagate from the output future to a callable that has begun to
   * execute, but if the output future is cancelled before {@link Callable#call()} is invoked,
   * {@link Callable#call()} will not be invoked.
   */
  public <T extends @Nullable Object> ListenableFuture<T> submit(
      Callable<T> callable, Executor executor) {
    checkNotNull(callable);
    checkNotNull(executor);
    return submitAsync(

from typing import Annotated, Any, Callable

from annotated_doc import Doc
from starlette.background import BackgroundTasks as StarletteBackgroundTasks
from typing_extensions import ParamSpec

P = ParamSpec("P")


class BackgroundTasks(StarletteBackgroundTasks):
    """
    A collection of background tasks that will be called after a response has been
    sent to the client.

    Read more about it in the

client = TestClient(app)


@pytest.mark.parametrize(
    "route,value",
    [
        ("/callable-dependency", "callable-dependency"),
        ("/callable-gen-dependency", "callable-gen-dependency"),
        ("/async-callable-dependency", "async-callable-dependency"),
        ("/async-callable-gen-dependency", "async-callable-gen-dependency"),
        ("/synchronous-method-dependency", "synchronous-method-dependency"),

Eine Python-Klasse ist also auch ein **Callable**.

Darum können Sie in **FastAPI** auch eine Python-Klasse als Abhängigkeit verwenden.

Was FastAPI tatsächlich prüft, ist, ob es sich um ein „Callable“ (Funktion, Klasse oder irgendetwas anderes) handelt und ob die Parameter definiert sind.

        ("/partial-callable-dependency", "partial-callable-dependency"),
        ("/partial-callable-gen-dependency", "partial-callable-gen-dependency"),
        ("/partial-async-callable-dependency", "partial-async-callable-dependency"),
        (
            "/partial-async-callable-gen-dependency",
            "partial-async-callable-gen-dependency",
        ),
        (