}
      return if (provider.unsupported) null else provider.selected
    } catch (e: InvocationTargetException) {
      throw AssertionError("failed to get ALPN selected protocol", e)
    } catch (e: IllegalAccessException) {
      throw AssertionError("failed to get ALPN selected protocol", e)
    }
  }

  /**
   * Handle the methods of ALPN's ClientProvider and ServerProvider without a compile-time

      countReload.incrementAndGet();
      return immediateFuture(oldValue + 1);
    }

    public int getLoadCount() {
      return countLoad.get();
    }

    public int getReloadCount() {
      return countReload.get();
    }
  }

  static final class IdentityLoader<T> extends CacheLoader<T, T> {
    @Override
    public T load(T key) {
      return key;
    }
  }

    Predicate<Throwable> predicate = INSTANCE_OF.get(expectedThrowable);
    if (predicate == null) {
      throw new IllegalArgumentException(
          expectedThrowable
              + " is not yet supported by ReflectionFreeAssertThrows. Add an entry for it in the"
              + " map in that class.");
    }
    Object result;
    try {
      result = supplier.get();
    } catch (Throwable t) {

//
// This is a `MetricsLoaderFn`.
func loadClusterUsageObjectMetrics(ctx context.Context, m MetricValues, c *metricsCache) error {
	dataUsageInfo, err := c.dataUsageInfo.Get()
	if err != nil {
		metricsLogIf(ctx, err)
		return nil
	}

	// data usage has not captured any data yet.
	if dataUsageInfo.LastUpdate.IsZero() {
		return nil
	}

	var (

    * 数据库模型。
    * ……以及更多。
* 自动生成的交互式 API 文档，包括两种可选的用户界面：
    * Swagger UI。
    * ReDoc。

---

回到之前的代码示例，**FastAPI** 将会：

* 校验 `GET` 和 `PUT` 请求的路径中是否包含 `item_id`。
* 校验 `GET` 和 `PUT` 请求中的 `item_id` 是否为 `int` 类型。
    * 如果不是，客户端会看到清晰有用的错误信息。
* 对于 `GET` 请求，检查是否存在名为 `q` 的可选查询参数（如 `http://127.0.0.1:8000/items/foo?q=somequery`）。
    * 因为参数 `q` 被声明为 `= None`，所以它是可选的。
    * 如果没有 `None`，它就是必需的（就像 `PUT` 情况下的请求体）。

        runningField.setAccessible(true);
        ((AtomicBoolean) runningField.get(null)).set(false);

        Field errorsField = Crawler.class.getDeclaredField("errors");
        errorsField.setAccessible(true);
        ((Queue<?>) errorsField.get(null)).clear();
    }

    // Test addError method
    @Test
    public void test_addError_withValidMessage() {

    val shadowPackagePrefix =
        shadowPackage.takeIf(String::isNotEmpty)
            ?.let { it.replace('.', '/') + "/" }
            ?: ""

    operator fun get(className: String) =
        classes.computeIfAbsent(className) {
            val outputClassName = if (unshadedPackages.matches(className)) className else shadowPackagePrefix + className

    super(unfiltered, predicate);
  }

  @Override
  public SetMultimap<K, V> unfiltered() {
    return (SetMultimap<K, V>) unfiltered;
  }

  @Override
  public Set<V> get(@ParametricNullness K key) {
    return (Set<V>) super.get(key);
  }

  @Override
  public Set<V> removeAll(@Nullable Object key) {
    return (Set<V>) super.removeAll(key);
  }

  @Override

    }

    @Override
    public Server getServer() {
        return servers.isEmpty() ? null : servers.get(0);
    }

    @Override
    public List<Server> getServers() {
        return servers;
    }

    @Override
    public Proxy getProxy() {
        return proxies.isEmpty() ? null : proxies.get(0);
    }

    @Override
    public List<Proxy> getProxies() {
        return proxies;
    }

     * @throws CIFSException if there is an error resolving the SIDs
     */
    void resolveSids(CIFSContext tc, String authorityServerName, SID[] sids, int off, int len) throws CIFSException;

    /**
     * Gets the SIDs of members of a group.
     *
     * @param tc the CIFS context to use
     * @param authorityServerName the server to use for resolution
     * @param domsid the domain SID
     * @param rid the group RID