* given object is also a multiset and contains equal elements with equal counts, regardless of
   * order.
   */
  @Override
  // TODO(kevinb): caveats about equivalence-relation?
  boolean equals(@Nullable Object object);

  /**
   * Returns the hash code for this multiset. This is defined as the sum of
   *
   * {@snippet :

     Licensor. For purposes of this Public License, where the Licensed
     Material is a musical work, performance, or sound recording,
     Adapted Material is always produced where the Licensed Material is
     synched in timed relation with a moving image.

  b. Adapter's License means the license You apply to Your Copyright
     and Similar Rights in Your contributions to Adapted Material in

   *   <li>The {@link Predicate} returned by this method catches {@link ClassCastException} and
   *       {@link NullPointerException}.
   *   <li>Code that chains multiple predicates together (especially negations) may be more readable
   *       using this method. For example, {@code not(in(target))} is generally more readable than
   *       {@code not(target::contains)}.

**FastAPI**は<a href="https://docs.pydantic.dev/" class="external-link" target="_blank"><strong>Pydantic </strong></a>と完全に互換性があります（そしてベースになっています）。したがって、追加のPydanticコードがあれば、それも機能します。

データベースのために<abbr title = "Object-Relational Mapper">ORM</abbr>sや、<abbr title = "Object-Document Mapper">ODM</abbr>sなどの、Pydanticに基づく外部ライブラリを備えています。

これは、すべてが自動的に検証されるため、多くの場合、リクエストから取得したオブジェクトを**データベースに直接**渡すことができるということを意味しています。

   * given object is also a multiset and contains equal elements with equal counts, regardless of
   * order.
   */
  @Override
  // TODO(kevinb): caveats about equivalence-relation?
  boolean equals(@Nullable Object object);

  /**
   * Returns the hash code for this multiset. This is defined as the sum of
   *
   * {@snippet :

/// tip | Consejo

Puedes usar cualquier otro paquete de bases de datos SQL o NoSQL que quieras (en algunos casos llamadas <abbr title="Object Relational Mapper, un término elegante para un paquete donde algunas clases representan tablas SQL y las instances representan filas en esas tablas">"ORMs"</abbr>), FastAPI no te obliga a usar nada. 😎

///

## Pydantic 特性

**FastAPI** 完全相容且基於 <a href="https://docs.pydantic.dev/" class="external-link" target="_blank"><strong>Pydantic</strong></a>。所以，你有其他 Pydantic 程式碼也能正常工作。

相容包括基於 Pydantic 的外部函式庫， 例如用於資料庫的 <abbr title="Object-Relational Mapper">ORM</abbr>s, <abbr title="Object-Document Mapper">ODM</abbr>s。

這也意味著在很多情況下，你可以把從請求中獲得的物件**直接傳到資料庫**，因為所有資料都會自動進行驗證。

反之亦然，在很多情況下，你也可以把從資料庫中獲取的物件**直接傳給客戶端**。

/// tip | 팁

다른 SQL 또는 NoSQL 데이터베이스 라이브러리를 사용할 수도 있습니다 (일부는 <abbr title="객체 관계 매퍼(Object Relational Mapper), SQL 테이블을 나타내는 클래스를 제공하고 테이블의 행을 인스턴스로 표현하는 라이브러리를 지칭하는 용어">"ORM"</abbr>이라고도 불립니다), FastAPI는 특정 라이브러리의 사용을 강요하지 않습니다. 😎

///

It's the most popular Python framework and is widely trusted. It is used to build systems like Instagram.

It's relatively tightly coupled with relational databases (like MySQL or PostgreSQL), so, having a NoSQL database (like Couchbase, MongoDB, Cassandra, etc) as the main store engine is not very easy.

import java.util.concurrent.atomic.AtomicReferenceArray;
import java.util.logging.LogRecord;
import junit.framework.TestCase;
import org.jspecify.annotations.NullUnmarked;

/**
 * Tests relating to cache loading: concurrent loading, exceptions during loading, etc.
 *
 * @author mike nonemacher
 */
@NullUnmarked
public class CacheLoadingTest extends TestCase {
  TestLogHandler logHandler;

  @Override