IdClass (Java EE 5 SDK)

Java

previous page next page

概述

软件包

类

树

已过时

索引

帮助

Java EE 5 SDK

深圳电信培训中心.徐海蛟老师.

上一个类 下一个类

框架 无框架

摘要: REQUIRED | OPTIONAL

详细信息: ELEMENT

javax.persistence Annotation Type IdClass

@Target(value=TYPE) @Retention(value=RUNTIME) public @interface IdClass

Specifies a composite primary key class that is mapped to multiple fields or properties of the entity.

The names of the fields or properties in the primary key class and the primary key fields or properties of the entity must correspond and their types must be the same.


   Example:

   @IdClass(com.acme.EmployeePK.class)
   @Entity
   public class Employee {
     @Id String empName;
     @Id Date birthDay;
     ...
   }