}

  private @Nullable Object[] requireValues() {
    return requireNonNull(values);
  }

  /*
   * The following methods are safe to call as long as the conditions in the *previous* comment are
   * met *and* the index is less than size().
   *
   * (The above explains when these methods are safe from a `nullness` perspective. From an

没有前人的工作，就不会有 **FastAPI**。

在它诞生之前，已经有许多工具为其提供了灵感。

我曾经多年避免创建一个新框架。起初，我尝试用许多不同的框架、插件和工具来解决 **FastAPI** 所覆盖的全部功能。

但在某个时刻，除了创造一个能提供所有这些功能的东西之外，别无选择；它要吸收以往工具的最佳理念，并以尽可能好的方式组合起来，利用之前都不存在的语言特性（Python 3.6+ 类型提示）。

## 先前的工具 { #previous-tools }

### [Django](https://www.djangoproject.com/) { #django }

它是最流行且被广泛信任的 Python 框架。被用于构建 Instagram 等系统。

它与关系型数据库（如 MySQL、PostgreSQL）耦合相对紧密，因此若要以 NoSQL 数据库（如 Couchbase、MongoDB、Cassandra 等）作为主要存储引擎并不容易。

   * {@code join("-", 1.0f, 2.0f, 3.0f)} returns the string {@code "1.0-2.0-3.0"}.
   *
   * <p>Note that {@link Float#toString(float)} formats {@code float} differently in GWT. In the
   * previous example, it returns the string {@code "1-2-3"}.
   *
   * @param separator the text that should appear between consecutive values in the resulting string
   *     (but not at the start or end)

  private final TearDownStack tearDownStack = new TearDownStack();

  // NOTE: All durations in these tests are expressed in milliseconds
  @Override
  protected void setUp() {
    // Clear any previous interrupt before running the test.
    if (Thread.currentThread().isInterrupted()) {
      throw new AssertionError(
          "Thread interrupted on test entry. "

      }
      // reset for next iteration
      setFutureSuccess.set(false);
      cancellationSuccess.set(false);
      finalResults.clear();
    }
    executor.shutdown();
  }

  // In a previous implementation this would cause a stack overflow after ~2000 futures chained
  // together.  Now it should only be limited by available memory (and time)
  public void testSetFuture_stackOverflow() {

   * old Android Ice Cream Sandwich release), then this method throws an exception instead of
   * creating a directory that would be more accessible. (This behavior is new in Guava 32.0.0.
   * Previous versions would create a directory that is more accessible, as discussed in <a
   * href="https://github.com/google/guava/issues/4011">CVE-2020-8908</a>.)
   *

        // Simple connectivity test
        return client != null && client.isConnected();
    }
    
    private void reregisterNotifications() {
        // Re-register all previous registrations
        // Implementation would store registration details for recovery
    }
}
```

### 8.2 Network Partition Handling
```java
public class WitnessNetworkPartitionHandler {

 * If you use masked losses with Keras the loss values may be different in TensorFlow `2.12` compared to previous versions.
 * In cases where the mask was previously ignored, you will now get an error if you pass a mask with an incompatible shape.

   * {@code join("-", 1.0, 2.0, 3.0)} returns the string {@code "1.0-2.0-3.0"}.
   *
   * <p>Note that {@link Double#toString(double)} formats {@code double} differently in GWT
   * sometimes. In the previous example, it returns the string {@code "1-2-3"}.
   *
   * @param separator the text that should appear between consecutive values in the resulting string
   *     (but not at the start or end)

 *     Ordering.natural()
 *         .nullsFirst()
 *         .onResultOf(getBarFunction)
 *         .nullsLast();
 * }
 *
 * Note that each chaining method returns a new ordering instance which is backed by the previous
 * instance, but has the chance to act on values <i>before</i> handing off to that backing instance.
 * As a result, it usually helps to read chained ordering expressions <i>backwards</i>. For example,