import java.util.LinkedHashSet;
import java.util.List;
import java.util.Locale;
import java.util.Map;
import java.util.Queue;
import java.util.Set;
import org.jspecify.annotations.NullMarked;

/**
 * Utilities for collecting and validating tester requirements from annotations.
 *
 * @author George van den Driessche
 */
@GwtIncompatible
public final class FeatureUtil {

{* ../../docs_src/handling_errors/tutorial002_py310.py hl[14] *}

## Install custom exception handlers { #install-custom-exception-handlers }

You can add custom exception handlers with [the same exception utilities from Starlette](https://www.starlette.dev/exceptions/).

Let's say you have a custom exception `UnicornException` that you (or a library you use) might `raise`.

And you want to handle this exception globally with FastAPI.

/**
 * DefaultContentsParser is an implementation of the ContentsParser interface.
 * It provides methods to parse search words, query logs, and documents into SuggestItem objects.
 *
 * <p>This class uses various utilities such as ReadingConverter, Normalizer, and SuggestAnalyzer
 * to process and analyze the input data.</p>
 *
 * <p>It also handles the exclusion of search words based on certain criteria and manages the

import java.util.Optional;
import java.util.stream.Collector;
import org.jspecify.annotations.Nullable;

/**
 * Provides static methods for working with {@link Comparator} instances. For many other helpful
 * comparator utilities, see either {@code Comparator} itself (for Java 8+), or {@code
 * com.google.common.collect.Ordering} (otherwise).
 *
 * <h3>Relationship to {@code Ordering}</h3>
 *

Pydantic model is included in the **OpenAPI** of your API, and then it's used in the docs UI.

In versions of FastAPI before 0.99.0 (0.99.0 and above use the newer OpenAPI 3.1.0) when you used `example` or `examples` with any of the other utilities (`Query()`, `Body()`, etc.) those examples were not added to the JSON Schema that describes that data (not even to OpenAPI's own version of JSON Schema), they were added directly to the *path operation* declaration in OpenAPI (outside the parts of...

import java.util.Optional;
import java.util.stream.Collector;
import org.jspecify.annotations.Nullable;

/**
 * Provides static methods for working with {@link Comparator} instances. For many other helpful
 * comparator utilities, see either {@code Comparator} itself (for Java 8+), or {@code
 * com.google.common.collect.Ordering} (otherwise).
 *
 * <h3>Relationship to {@code Ordering}</h3>
 *

Google、Facebook、X (Twitter)、GitHubなど、他の認証/認可プロバイダを統合することも可能で、比較的簡単です。

最も複雑な問題は、それらのような認証/認可プロバイダを構築することですが、**FastAPI**は、あなたのために重い仕事をこなしながら、それを簡単に行うためのツールを提供します。

///

## **FastAPI** ユーティリティ { #fastapi-utilities }

FastAPIは `fastapi.security` モジュールの中で、これらのセキュリティスキームごとにいくつかのツールを提供し、これらのセキュリティメカニズムを簡単に使用できるようにします。

次の章では、**FastAPI** が提供するこれらのツールを使って、あなたのAPIにセキュリティを追加する方法について見ていきます。

import java.util.stream.Stream;
import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/**
 * Supplies an arbitrary "default" instance for a wide range of types, often useful in testing
 * utilities.
 *
 * <p>Covers arrays, enums and common types defined in {@code java.lang}, {@code java.lang.reflect},
 * {@code java.io}, {@code java.nio}, {@code java.math}, {@code java.util}, {@code

import java.util.concurrent.TimeoutException;
import java.util.concurrent.locks.AbstractQueuedSynchronizer;
import org.jspecify.annotations.NullUnmarked;
import org.jspecify.annotations.Nullable;

/** Utilities for the AbstractFutureBenchmarks */
@NullUnmarked
@GwtIncompatible
@J2ktIncompatible
final class AbstractFutureBenchmarks {
  private AbstractFutureBenchmarks() {}

  interface Facade<T> extends ListenableFuture<T> {

import java.util.function.Supplier;
import java.util.function.ToIntFunction;
import java.util.stream.Collector;
import java.util.stream.Stream;
import org.jspecify.annotations.Nullable;

/** Collectors utilities for {@code common.collect} internals. */
@GwtCompatible
@IgnoreJRERequirement // used only from APIs with Java 8 types in them
final class CollectCollectors {