* asynchronous handling, message chaining, cancellation, and timeout management.
 *
 * @author mbechler
 */
public interface CommonServerMessageBlockRequest extends CommonServerMessageBlock, Request {

    /**
     * Checks if the request will be handled asynchronously.
     *
     * @return request was handled asynchronously
     */
    boolean isResponseAsync();

    /**
     *
     * @return next chained message
     */

このようにして依存関係を「パラメータ化」できます。いまや `"bar"` が属性 `checker.fixed_content` として中に保持されています。

## インスタンスを依存関係として使う { #use-the-instance-as-a-dependency }

その後、`Depends(FixedContentQueryChecker)` の代わりに `Depends(checker)` でこの `checker` を使えます。依存関係はクラスそのものではなく、インスタンスである `checker` だからです。

依存関係を解決するとき、**FastAPI** はこの `checker` を次のように呼び出します:

```Python
checker(q="somequery")
```

But you might want to still keep the return type annotation in the function to get the support from tools like editors and type checkers (e.g. mypy).

In this case, you can disable the response model generation by setting `response_model=None`:

{* ../../docs_src/response_model/tutorial003_05_py310.py hl[7] *}

      queue.add(submittedTask);
      workerRunningState = QUEUING;
    }

    try {
      executor.execute(worker);
    } catch (Throwable t) {
      // Any Exception is either a RuntimeException or sneaky checked exception.
      synchronized (queue) {
        boolean removed =
            (workerRunningState == IDLE || workerRunningState == QUEUING)
                && queue.removeLastOccurrence(submittedTask);

        assertEquals(runtimeException, exception.getCause());
    }

    @Test
    public void test_constructorWithThrowableCause_CheckedException() {
        // Test with checked exception (IOException)
        String message = "IO error during thumbnail generation";
        Exception checkedException = new java.io.IOException("File not found");

{* ../../docs_src/dependencies/tutorial011_an_py310.py hl[18] *}

这样就把依赖项“参数化”了，现在它内部带有属性 `checker.fixed_content` 的值 `"bar"`。

## 把实例作为依赖项 { #use-the-instance-as-a-dependency }

然后，我们可以在 `Depends(checker)` 中使用这个 `checker`，而不是 `Depends(FixedContentQueryChecker)`，因为依赖项是实例 `checker`，不是类本身。

解析依赖项时，**FastAPI** 会像这样调用 `checker`：

```Python
checker(q="somequery")
```

...并将其返回值作为依赖项的值，传给我们的*路径操作函数*中的参数 `fixed_content_included`：

on:
  # For Branch-Protection check. Only the default branch is supported. See
  # https://github.com/ossf/scorecard/blob/main/docs/checks.md#branch-protection
  branch_protection_rule:
  # To guarantee Maintained check is occasionally updated. See
  # https://github.com/ossf/scorecard/blob/main/docs/checks.md#maintained
  schedule:
    - cron: '26 3 * * 2'
  push:
    branches: [ "master" ]

# Declare default permissions as read only.

   * fact the static type of {@link Throwable} is occasionally justified even for a method with no
   * {@code throws} clause: Some such methods can in fact throw a checked exception (e.g., by
   * calling code written in Kotlin).) Typically, we want to let a {@link Throwable} from such a
   * method propagate untouched, just as we'd typically let it do for a non-reflective call.

   * fact the static type of {@link Throwable} is occasionally justified even for a method with no
   * {@code throws} clause: Some such methods can in fact throw a checked exception (e.g., by
   * calling code written in Kotlin).) Typically, we want to let a {@link Throwable} from such a
   * method propagate untouched, just as we'd typically let it do for a non-reflective call.

    public T get() {
      // A 2-field variant of Double Checked Locking.
      if (!initialized) {
        synchronized (lock) {
          if (!initialized) {
            T t = delegate.get();
            value = t;
            initialized = true;
            return t;
          }
        }
      }
      // This is safe because we checked `initialized`.
      return uncheckedCastNullableTToT(value);
    }