程序包 org.hibernate.annotations

枚举 FetchMode

  • 所有已实现的接口:
    Serializable, Comparable<FetchMode>
    public enum FetchMode
extends Enum<FetchMode>
    Fetch options on associations. Defines more of the "how" of fetching, whereas JPA FetchType focuses on the "when".
    作者:
    Emmanuel Bernard

    • 枚举常量详细资料

      • SELECT

        public static final FetchMode SELECT
        Use a secondary select for each individual entity, collection, or join load.

      • JOIN

        public static final FetchMode JOIN
        Use an outer join to load the related entities, collections or joins.

      • SUBSELECT

        public static final FetchMode SUBSELECT
        Available for collections only.  When accessing a non-initialized collection, this fetch mode will trigger loading all elements of all collections of the same role for all owners associated with the persistence context using a single secondary select.

    • 方法详细资料

      • values

        public static FetchMode[] values()
        按照声明该枚举类型的常量的顺序, 返回 包含这些常量的数组。该方法可用于迭代 常量, 如下所示: 
        for (FetchMode c : FetchMode.values())
    System.out.println(c);
        返回:
        按照声明该枚举类型的常量的顺序返回的包含这些常量的数组

      • valueOf

        public static FetchMode valueOf​(String name)
        返回带有指定名称的该类型的枚举常量。 字符串必须与用于声明该类型的枚举常量的 标识符完全匹配。(不允许有多余 的空格字符。)
        参数:
        name - 要返回的枚举常量的名称。
        返回:
        返回带有指定名称的枚举常量
        抛出:
        IllegalArgumentException - 如果该枚举类型没有带有指定名称的常量
        NullPointerException - 如果参数为空值