if (tempDir == null) {
      tempDir = createTempDir();
    }

    return tempDir;
  }

  /**
   * Creates a new temp file in the temp directory returned by {@link #getTempDir()}. The file will
   * be deleted in the tear-down for this test.
   */
  protected final File createTempFile() throws IOException {
    return File.createTempFile("test", null, getTempDir());
  }

import java.util.concurrent.CountDownLatch;
import java.util.concurrent.atomic.AtomicBoolean;
import junit.framework.TestCase;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Tests for {@link GcFinalization}.
 *
 * @author Martin Buchholz
 * @author mike nonemacher
 */
@AndroidIncompatible // depends on details of gc

public class GcFinalizationTest extends TestCase {

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

/**
 * Test cases for a {@link Table} implementation supporting reads and writes.
 *
 * @author Jared Levy
 * @author Louis Wasserman
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault

import java.io.IOException;
import java.io.PrintWriter;
import java.net.URL;
import java.net.URLClassLoader;
import java.util.ArrayList;
import java.util.List;
import junit.framework.TestSuite;

/**
 * Unit test for {@link Resources}.
 *
 * @author Chris Nokleberg
 */

public class ResourcesTest extends IoTestCase {

  @AndroidIncompatible // wouldn't run anyway, but strip the source entirely because of b/230620681

import com.google.errorprone.annotations.Immutable;
import java.io.Serializable;
import java.nio.ByteBuffer;
import javax.annotation.CheckForNull;

/**
 * {@link HashFunction} implementation of SipHash-c-d.
 *
 * @author Kurt Alfred Kluever
 * @author Jean-Philippe Aumasson
 * @author Daniel J. Bernstein
 */
@Immutable
@ElementTypesAreNonnullByDefault

## OpenAPI 客户端生成

有许多工具可以从**OpenAPI**生成客户端。

一个常见的工具是 <a href="https://openapi-generator.tech/" class="external-link" target="_blank">OpenAPI Generator</a>。

如果您正在开发**前端**，一个非常有趣的替代方案是 <a href="https://github.com/hey-api/openapi-ts" class="external-link" target="_blank">openapi-ts</a>。

## 生成一个 TypeScript 前端客户端

让我们从一个简单的 FastAPI 应用开始：

//// tab | Python 3.9+

```Python hl_lines="7"
{!../../docs_src/query_params_str_validations/tutorial006b.py!}
```

/// info

如果你之前没见过 `...` 这种用法：它是一个特殊的单独值，它是 <a href="https://docs.python.org/3/library/constants.html#Ellipsis" class="external-link" target="_blank">Python 的一部分并且被称为「省略号」</a>。
Pydantic 和 FastAPI 使用它来显式的声明需要一个值。

///

这将使 **FastAPI** 知道此查询参数是必需的。

### 使用`None`声明必需参数

你可以声明一个参数可以接收`None`值，但它仍然是必需的。这将强制客户端发送一个值，即使该值是`None`。

)
```

/// info | Informação

Para uma explicação mais completa de `**user_dict`, verifique [a documentação para **Extra Models**](../extra-models.md#about-user_indict){.internal-link target=_blank}.

///

## Retorne o token

A resposta do endpoint `token` deve ser um objeto JSON.

      represent, as a whole, an original work of authorship. For the purposes
      of this License, Derivative Works shall not include works that remain
      separable from, or merely link (or bind by name) to the interfaces of,
      the Work and Derivative Works thereof.

      "Contribution" shall mean any work of authorship, including
      the original version of the Work and any modifications or additions

"Strong"};c&&a.extend(d,c),b.bind("keyup",function(){var b=a(this).val(),c="undefined"==typeof d.parent?a(this).parent():a(d.parent),e=c.find(".strength-meter"),f=a.formUtils.validators.validate_strength.calculatePasswordStrength(b),g={background:"pink",color:"#FF0000",fontWeight:"bold",border:"red solid 1px",borderWidth:"0px 0px 4px",display:"inline-block",fontSize:d.fontSize,padding:d.padding},h=d.bad;0===e.length&&(e=a("<span></span>"),e.addClass("strength-meter").appendTo(c)),b?e.show():e.hi...