assertThat(Enums.getIfPresent(TestEnum.class, "POODLE")).hasValue(TestEnum.POODLE);

    assertThat(Enums.getIfPresent(TestEnum.class, "CHEETO")).isPresent();
    assertThat(Enums.getIfPresent(TestEnum.class, "HONDA")).isPresent();
    assertThat(Enums.getIfPresent(TestEnum.class, "POODLE")).isPresent();

    assertThat(Enums.getIfPresent(TestEnum.class, "CHEETO")).hasValue(TestEnum.CHEETO);

 *   <li>{@link Strings}
 * </ul>
 *
 * <h3>Function types</h3>
 *
 * <ul>
 *   <li>{@link Converter}
 *   <li>{@link Equivalence}
 * </ul>
 *
 * <h3>Other</h3>
 *
 * <ul>
 *   <li>{@link Enums}
 *   <li>{@link MoreObjects}
 *   <li>{@link Preconditions}
 *   <li>{@link StandardSystemProperty}
 *   <li>{@link Stopwatch}
 *   <li>{@link Throwables}
 *   <li>{@link Verify}
 * </ul>
 *

    assertThat(Enums.getIfPresent(TestEnum.class, "POODLE")).hasValue(TestEnum.POODLE);

    assertThat(Enums.getIfPresent(TestEnum.class, "CHEETO")).isPresent();
    assertThat(Enums.getIfPresent(TestEnum.class, "HONDA")).isPresent();
    assertThat(Enums.getIfPresent(TestEnum.class, "POODLE")).isPresent();

    assertThat(Enums.getIfPresent(TestEnum.class, "CHEETO")).hasValue(TestEnum.CHEETO);

 *   <li>{@link Strings}
 * </ul>
 *
 * <h3>Function types</h3>
 *
 * <ul>
 *   <li>{@link Converter}
 *   <li>{@link Equivalence}
 * </ul>
 *
 * <h3>Other</h3>
 *
 * <ul>
 *   <li>{@link Enums}
 *   <li>{@link MoreObjects}
 *   <li>{@link Preconditions}
 *   <li>{@link StandardSystemProperty}
 *   <li>{@link Stopwatch}
 *   <li>{@link Throwables}
 *   <li>{@link Verify}
 * </ul>
 *

     * @throws IllegalAccessRuntimeException if the number of actual and formal parameters differ, if primitive arguments cannot be converted, or if the class is related to enums
     * @see Constructor#newInstance(Object[])
     */
    public static <T> T newInstance(final Constructor<T> constructor, final Object... args)
            throws InstantiationRuntimeException, IllegalAccessRuntimeException {

	public static final field HEADERS Lokhttp3/logging/HttpLoggingInterceptor$Level;
	public static final field NONE Lokhttp3/logging/HttpLoggingInterceptor$Level;
	public static fun getEntries ()Lkotlin/enums/EnumEntries;
	public static fun valueOf (Ljava/lang/String;)Lokhttp3/logging/HttpLoggingInterceptor$Level;
	public static fun values ()[Lokhttp3/logging/HttpLoggingInterceptor$Level;
}

import java.util.HashSet;
import java.util.Objects;
import java.util.Set;

/**
 * Utility class for creating extensible enum implementations.
 * This class provides factory methods for creating instances of extensible enums
 * such as Language, PathScope, and ProjectScope.
 *
 * @since 4.0.0
 */
abstract class ExtensibleEnums {

    /**
     * Creates a new Language instance with the specified ID.
     *

{* ../../docs_src/path_operation_configuration/tutorial002_py310.py hl[15,20,25] *}

這些標籤會被加入到 OpenAPI 結構描述，並由自動化文件介面使用：

<img src="/img/tutorial/path-operation-configuration/image01.png">

### 含 Enum 的標籤 { #tags-with-enums }

如果你的應用很大，可能會累積數個標籤，你會希望對相關的「路徑操作」始終使用相同的標籤。

在這種情況下，可以考慮把標籤存放在 `Enum` 中。

**FastAPI** 對此的支援方式與使用普通字串相同：

{* ../../docs_src/path_operation_configuration/tutorial002b_py310.py hl[1,8:10,13,18] *}

    return new MultimapBuilderWithKeys<K0>() {
      @SuppressWarnings("unchecked")
      @Override
      <K extends K0, V extends @Nullable Object> Map<K, Collection<V>> createMap() {
        // K must actually be K0, since enums are effectively final
        // (their subclasses are inaccessible)
        return (Map<K, Collection<V>>) new EnumMap<K0, Collection<V>>(keyClass);
      }
    };
  }

    return new MultimapBuilderWithKeys<K0>() {
      @SuppressWarnings("unchecked")
      @Override
      <K extends K0, V extends @Nullable Object> Map<K, Collection<V>> createMap() {
        // K must actually be K0, since enums are effectively final
        // (their subclasses are inaccessible)
        return (Map<K, Collection<V>>) new EnumMap<K0, Collection<V>>(keyClass);
      }
    };
  }