* use a framework. Frameworks automate the process, often adding features like monitoring,
 * debugging, and cancellation. Examples of frameworks include:
 *
 * <ul>
 *   <li><a href="https://dagger.dev/producers.html">Dagger Producers</a>
 * </ul>
 *
 * <h4>{@link java.util.concurrent.CompletableFuture} / {@link java.util.concurrent.CompletionStage}
 * </h4>
 *

That way the session would release the database connection, so other requests could use it.

再一次，仅仅进行这样的声明，你将通过 **FastAPI** 获得：

* 对被嵌入的模型也适用的编辑器支持（自动补全等）
* 数据转换
* 数据校验
* 自动生成文档

## 特殊的类型和校验

除了普通的单一值类型（如 `str`、`int`、`float` 等）外，你还可以使用从 `str` 继承的更复杂的单一值类型。

要了解所有的可用选项，请查看关于 <a href="https://docs.pydantic.dev/latest/concepts/types/" class="external-link" target="_blank">来自 Pydantic 的外部类型</a> 的文档。你将在下一章节中看到一些示例。

例如，在 `Image` 模型中我们有一个 `url` 字段，我们可以把它声明为 Pydantic 的 `HttpUrl`，而不是 `str`：

 * read operations will work correctly. To allow concurrent update operations, wrap your multimap
 * with a call to {@link Multimaps#synchronizedSortedSetMultimap}.
 *
 * <p>See the Guava User Guide article on <a href=
 * "https://github.com/google/guava/wiki/NewCollectionTypesExplained#multimap">{@code Multimap}</a>.
 *
 * @author Jared Levy
 * @author Louis Wasserman
 * @since 2.0
 */
@GwtCompatible

 * <i>if and only if</i> {@code a.equals(b)}. If this advice is not followed, the resulting
 * collection will not correctly obey its specification.
 *
 * <p>See the Guava User Guide article on <a href=
 * "https://github.com/google/guava/wiki/ImmutableCollectionsExplained">immutable collections</a>.
 *
 * @author Louis Wasserman
 * @since 12.0
 */
@GwtIncompatible // hasn't been tested yet

ame</code></td><td><code>str</code></td><td><strong>ERFORDERLICH</strong> (wenn eine <code>license_info</code> festgelegt ist). Der für die API verwendete Lizenzname.</td></tr><tr><td><code>identifier</code></td><td><code>str</code></td><td>Ein <a href="https://spdx.org/licenses/" class="external-link" target="_blank">SPDX</a>-Lizenzausdruck für die API. Das Feld <code>identifier</code> und das Feld <code>url</code> schließen sich gegenseitig aus. <small>Verfügbar seit OpenAPI 3.1.0, FastAPI 0.9...

de>str</code></td><td><strong>REQUERIDO</strong> (si se establece un <code>license_info</code>). El nombre de la licencia utilizada para la API.</td></tr><tr><td><code>identifier</code></td><td><code>str</code></td><td>Una expresión de licencia <a href="https://spdx.org/licenses/" class="external-link" target="_blank">SPDX</a> para la API. El campo <code>identifier</code> es mutuamente excluyente del campo <code>url</code>. <small>Disponible desde OpenAPI 3.1.0, FastAPI 0.99.0.</small></td></tr>...

/**
 * A sorted multiset which forwards all its method calls to another sorted multiset. Subclasses
 * should override one or more methods to modify the behavior of the backing multiset as desired per
 * the <a href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
 *
 * <p><b>Warning:</b> The methods of {@code ForwardingSortedMultiset} forward

import com.google.common.collect.Ordering;
import com.google.common.collect.Sets;
import com.google.common.testing.GcFinalization;
import com.google.common.testing.NullPointerTester;
import java.lang.ref.WeakReference;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.Semaphore;
import java.util.concurrent.locks.Lock;

import com.google.common.testing.NullPointerTester;
import com.google.common.testing.SerializableTester;
import java.io.File;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.ref.WeakReference;
import java.lang.reflect.Field;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLClassLoader;
import java.util.HashSet;
import java.util.Set;
import junit.framework.TestCase;