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JPA不支持很好的接口..影响?

jpa java

Aravind Yarram · 技术社区 · 15 年前

我在JPA的stackoverflow中浏览了一些帖子,我读了很多JPA不支持接口的地方。有人能分享一下它在现实世界中的意义吗?这是否意味着我们不能注释接口?

3 回复 | 直到 15 年前

James 15 年前

http://en.wikibooks.org/wiki/Java_Persistence/Advanced_Topics#Interfaces

Sean Patrick Floyd 15 年前

use @MappedSuperclass for inheritance

@MappedSuperclass
public abstract class BaseEntity implements Serializable {
    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Long id;
}

@MappedSuperclass
public abstract class ExtendedEntity extends BaseEntity{

    @Temporal(TemporalType.TIMESTAMP)
    private Date createdDate;

    @Temporal(TemporalType.TIMESTAMP)
    private Date updatedDate;

    @PrePersist
    protected void creationTimeStamp(){
        createdDate = new Date();
        this.updateTimeStamp();
    }

    @PreUpdate
    protected void updateTimeStamp(){
        updatedDate = new Date();
    }

}

BaseEntity ExtendedEntity

the way the inheritance is modeled

perhaps @Embeddable is the solution