* <ul>
 *   <li>{@link #expired()}: Handles the expiration of connections by closing expired and idle connections.</li>
 * </ul>
 *
 * <p>Logging:</p>
 * <ul>
 *   <li>Logs a warning if the clientConnectionManager is null.</li>
 *   <li>Logs a warning if an exception occurs during connection monitoring.</li>
 * </ul>
 *
 */
public class Hc5ConnectionMonitorTarget implements TimeoutTarget {

import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;
import org.jspecify.annotations.Nullable;

/**
 * {@link FluentFuture} that forwards all calls to a delegate.
 *
 * <p><b>Warning:</b> The methods of {@code ForwardingFluentFuture} forward <b>indiscriminately</b>
 * to the methods of the delegate. For example, overriding {@link #get(long, TimeUnit)} alone

## 匯入 `Field` { #import-field }

首先，你需要匯入它：

{* ../../docs_src/body_fields/tutorial001_an_py310.py hl[4] *}


/// warning

請注意，`Field` 是直接從 `pydantic` 匯入的，不像其他（如 `Query`、`Path`、`Body` 等）是從 `fastapi` 匯入。

///

## 宣告模型屬性 { #declare-model-attributes }

接著你可以在模型屬性上使用 `Field`：

 * should override one or more methods to modify the behavior of the backing future as desired per
 * the <a href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
 *
 * <p><b>Warning:</b> The methods of {@code ForwardingListenableFuture} forward
 * <b>indiscriminately</b> to the methods of the delegate. For example, overriding {@link #get(long,

 * <ul>
 *   <li>{@link #expired()}: Handles the expiration of connections by closing expired and idle connections.</li>
 * </ul>
 *
 * <p>Logging:</p>
 * <ul>
 *   <li>Logs a warning if the clientConnectionManager is null.</li>
 *   <li>Logs a warning if an exception occurs during connection monitoring.</li>
 * </ul>
 *
 */
public class Hc4ConnectionMonitorTarget implements TimeoutTarget {

        } else if (platformSystemProperty == JDK8_ALPN_PROPERTY) {
          if (!isAlpnBootEnabled()) {
            System.err.println("Warning: ALPN Boot not enabled")
          }
        } else if (platformSystemProperty == JDK8_PROPERTY) {
          if (isAlpnBootEnabled()) {
            System.err.println("Warning: ALPN Boot enabled unintentionally")
          }

/// warning

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We’re currently switching to an automated translation system 🤖, which will help keep all translations complete and up to date.

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与在*路径操作函数*中使用 `Query`、`Path` 、`Body` 声明校验与元数据的方式一样，可以使用 Pydantic 的 `Field` 在 Pydantic 模型内部声明校验和元数据。

## 导入 `Field` { #import-field }

首先，从 Pydantic 中导入 `Field`：

{* ../../docs_src/body_fields/tutorial001_an_py310.py hl[4] *}

/// warning | 警告

注意，与从 `fastapi` 导入 `Query`，`Path`、`Body` 不同，要直接从 `pydantic` 导入 `Field` 。

///

## 声明模型属性 { #declare-model-attributes }

然后，使用 `Field` 定义模型的属性：

- /// note | Technical Details»: /// note | Détails techniques
- /// note: /// note | Remarque
- /// tip: /// tip | Astuce
- /// warning: /// warning | Alertes
- /// check: /// check | Vérifications
- /// info: /// info

- the docs: les documents
- the documentation: la documentation

- Exclude from OpenAPI: Exclusion d'OpenAPI

 *
 * <p><b>Warning:</b> The methods of {@code ForwardingFuture} forward <b>indiscriminately</b> to the
 * methods of the delegate. For example, overriding {@link #get(long, TimeUnit)} alone <b>will
 * not</b> change the behavior of {@link #get()}, which can lead to unexpected behavior. In this
 * case, you should override {@code get()} as well.
 *