这个每次生成的uuid都是一样的，怎么整？？

@Entity
@Table(name = "SYSUSER")
public class SysUser implements Serializable {
    @Id
    @GenericGenerator(name = "userId", strategy = "uuid") //这个是hibernate的注解/生成32位UUID
    @GeneratedValue(generator = "userId")
    private String id;