我有一个与其他实体有关系的实体,而没有级联这样的东西:
@Entity
public class User {
//id
@Id
private Long id;
//fields
@Column(unique = true, nullable = false)
private String username;
@Column(nullable = false)
private String password;
@OneToMany(mappedBy = "owner")
private List<Address> addressList;
}
和这个实体:
@Entity
public class Address{
//id
@Id
private Long id;
//fields
private String title;
@Column(nullable = false)
private String location;
@ManyToOne(fetch = FetchType.LAZY, optional = false)
@JoinColumn(name = "owner_id")
private User owner;
}
在此示例中,我想创建一个地址,而无需从db重新获取用户,并使用jpa getReference,但我没有用户ID,只是用户名如何通过诸如用户名之类的唯一字段调用SpringJpaData getOne()? 有没有更好的选择来创建新地址而无需从数据库获取用户?