对于父类中的@Id和基类中的唯一序列，正确的JPA映射是什么? [英] What is the proper JPA mapping for @Id in parent and unique sequence in base classes

问题描述

我有一个类层次结构:

abstract DomainObject {
...
    @Id
    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator="SEQ")
    @SequenceGenerator(name="SEQ",sequenceName="SEQ_DB_NAME")
    @Column(name = "id", updatable = false, nullable = false)
    private Long id;
...
}

BaseClass extends DomainObject {
...
   // Fill in blank here where this class's @Id will use a unique sequence generator
   // bonus points for any sort of automatic assignment of generator names that might 
   //prevent me from having to instrument all my domain objects uniquely
...
}

注释:

• 我不是特别需要基类生成器，因此如果我应该删除它，就没问题了.
• 如果适用，这是一个oracle 9i数据库
• Hibernate 3.4 JPA
• Spring 2.5也可用

谢谢

推荐答案

好的，这就是我最终解决问题的方法:

Okay here's how I ended up solving the problem:

基类:

@MappedSuperclass
public abstract class DomainObject implements Serializable {
 @Id
 @GeneratedValue(strategy = GenerationType.SEQUENCE, generator="SEQ")
 @Column(name = "id", updatable = false, nullable = false)
 private Long id;

 .. rest of class
}

后代阶级:

@Entity
@SequenceGenerator(name="SEQ",sequenceName="SEQ_DB_NAME")
public class BusinessObject extends DomainObject {

 ...

}

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