FieldResult (Java EE 5)

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SUMMARY: REQUIRED | OPTIONAL

DETAIL: ELEMENT

javax.persistence Annotation Type FieldResult

@Target(value={}) @Retention(value=RUNTIME) public @interface FieldResult

Implements: Annotation

@Target(value={})
@Retention(value=RUNTIME)

此类用于将查询的 SELECT 列表中指定的列映射到实体类的属性或字段。

示例：
   Query q = em.createNativeQuery(
       "SELECT o.id AS order_id, " +
           "o.quantity AS order_quantity, " +
           "o.item AS order_item, " +
         "FROM Order o, Item i " +
         "WHERE (order_quantity > 25) AND (order_item = i.id)",
       "OrderResults");

   @SqlResultSetMapping(name="OrderResults",
       entities={
           @EntityResult(entityClass=com.acme.Order.class, fields={
               @FieldResult(name="id", column="order_id"),
               @FieldResult(name="quantity", column="order_quantity"),
               @FieldResult(name="item", column="order_item")})
       })

since

Java Persistence 1.0

英文文档：

Is used to map the columns specified in the SELECT list of the query to the properties or fields of the entity class.

 Example:
   Query q = em.createNativeQuery(
       "SELECT o.id AS order_id, " +
           "o.quantity AS order_quantity, " +
           "o.item AS order_item, " +
         "FROM Order o, Item i " +
         "WHERE (order_quantity > 25) AND (order_item = i.id)",
       "OrderResults");

   @SqlResultSetMapping(name="OrderResults",
       entities={
           @EntityResult(entityClass=com.acme.Order.class, fields={
               @FieldResult(name="id", column="order_id"),
               @FieldResult(name="quantity", column="order_quantity"),
               @FieldResult(name="item", column="order_item")})
       })

Since:: Java Persistence 1.0

Required Element Summary
`String`	`column` Name of the column in the SELECT clause - i.e., column aliases, if applicable.
`String`	`name` Name of the persistent field or property of the class.