*       RuntimeException} (though {@code get} implementations are discouraged from throwing such
   *       exceptions).
   * </ul>
   *
   * <p>The overall principle is to continue to treat every checked exception as a checked
   * exception, every unchecked exception as an unchecked exception, and every error as an error. In
   * addition, the cause of any {@code ExecutionException} is wrapped in order to ensure that the

## Die Instanz als Abhängigkeit verwenden

Dann könnten wir diesen `checker` in einem `Depends(checker)` anstelle von `Depends(FixedContentQueryChecker)` verwenden, da die Abhängigkeit die Instanz `checker` und nicht die Klasse selbst ist.

Und beim Auflösen der Abhängigkeit ruft **FastAPI** diesen `checker` wie folgt auf:

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

	if idxName != "idx_public_table_name" {
		t.Errorf("invalid index name generated, got %v", idxName)
	}

	chkName := ns.CheckerName("public.table", "name")
	if chkName != "chk_public_table_name" {
		t.Errorf("invalid checker name generated, got %v", chkName)
	}

	joinTable := ns.JoinTableName("user_languages")
	if joinTable != "public.user_languages" {
		t.Errorf("invalid join table generated, got %v", joinTable)
	}

import java.util.concurrent.CancellationException;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.TimeoutException;
import junit.framework.AssertionFailedError;
import org.checkerframework.checker.nullness.qual.Nullable;

/** Replacements for JUnit's {@code assertThrows} that work under GWT/J2CL. */
@GwtCompatible(emulated = true)
@ElementTypesAreNonnullByDefault
final class ReflectionFreeAssertThrows {

 */

package com.google.common.collect.testing;

import com.google.common.annotations.GwtCompatible;
import java.util.Collections;
import java.util.Iterator;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * A utility for testing an Iterator implementation by comparing its behavior to that of a "known
 * good" reference implementation. In order to accomplish this, it's important to test a great

import java.util.concurrent.CancellationException;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.TimeoutException;
import junit.framework.AssertionFailedError;
import org.checkerframework.checker.nullness.qual.Nullable;

/** Replacements for JUnit's {@code assertThrows} that work under GWT/J2CL. */
@GwtCompatible(emulated = true)
@ElementTypesAreNonnullByDefault
final class ReflectionFreeAssertThrows {

```Python hl_lines="16"
{!../../docs_src/dependencies/tutorial011.py!}
```

这样就可以**参数化**依赖项，它包含 `checker.fixed_content` 的属性 - `"bar"`。

## 把实例作为依赖项

然后，不要再在 `Depends(checker)` 中使用 `Depends(FixedContentQueryChecker)`， 而是要使用 `checker`，因为依赖项是类实例 - `checker`，不是类。

处理依赖项时，**FastAPI** 以如下方式调用 `checker`：

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

……并用*路径操作函数*的参数 `fixed_content_included` 返回依赖项的值：

```Python hl_lines="20"

    def __call__(self, q: str = ""):
        if q:
            return self.fixed_content in q
        return False


checker = FixedContentQueryChecker("bar")


@app.get("/query-checker/")
async def read_query_check(fixed_content_included: bool = Depends(checker)):

import com.google.j2objc.annotations.RetainedLocalRef;
import java.util.Set;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.Future;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * A future whose value is derived from a collection of input futures.
 *
 * @param <InputT> the type of the individual inputs
 * @param <OutputT> the type of the output (i.e. this) future

          "version": {
            "requires": "${jsr305.version}"
          }
        },
        {
          "group": "org.checkerframework",
          "module": "checker-qual",
          "version": {
            "requires": "${checker.version}"
          }
        },
        {
          "group": "com.google.errorprone",
          "module": "error_prone_annotations",
          "version": {