1. 数据实体类

@Entity
@Table(name = "ip_user")
@GenericGenerator(name = "jpa-uuid", strategy = "uuid") // name = "system-uuid"也能够
public class User implements Serializable {

@Id@GeneratedValue(generator = "jpa-uuid") //system-uuid同样@Column(length = 32)private String userId;...

}

留神@GenericGenerator(name = "jpa-uuid", strategy = "uuid") 和 @GeneratedValue(generator = "jpa-uuid") 两个注解是生成策略外围注解。

留神@GenericGenerator(name = "system-uuid", strategy = "uuid") 和 @GeneratedValue(generator = "system-uuid") 两个注解是生成策略外围注解。

  1. 数据库字段
  2. 执行save办法后

不须要给user.id字段设置值,jpa会主动生成uuid并作为它的主键增加到表中。