Question

我有两个实体：用户和包含（引用）用户的访客。用户：

@Entity
public class User {

    @Id
    @GeneratedValue(strategy = GenerationType.SEQUENCE)
    private long user_id;

    @Column(unique = true)
    private String email;
    @Column
    private String password;
    @Column
    private String name;
    @Column
    private String surname;
    ....
}

旅客：

@Entity
public class Guest {
    @Id
    @OneToOne
    @JoinColumn(name = "user_id_fk")
    private User user;

    private int visits;
    ...    
}

您可以猜到，我希望我的外键user_id（user_id_fk）是我的guest虚拟机的主键，但此代码似乎不起作用。任何帮助将不胜感激。

Answer 1

@PrimaryKeyJoinColumn可能有用（我不确定）

您的客座课程：

@Entity
public class Guest {
    @OneToOne
    @PrimaryKeyJoinColumn
    private User user;

    private int visits;
    ...    
}

但你应该寻找实施inheritance

Answer 2

提及@JoinColumn中的列名而不是外键约束名。

@OneToOne
@JoinColumn(name = "user_id")
private User user;

Answer 3

感谢Y. Tarion，我能够解决我的问题。

对于可能会觉得有帮助的人，我在这里发布我的代码：

用户：

@Entity
@Inheritance(strategy=InheritanceType.TABLE_PER_CLASS)
public class User {

    @Id
    @GeneratedValue(strategy = GenerationType.SEQUENCE)
    private long user_id;

    @Column(unique = true)
    private String email;
    @Column
    private String password;
    @Column
    private String name;
    @Column
    private String surname;
    //...constructors, getters and setters...
}

旅客：

@Entity
public class Guest extends User {

    private int visits;

    @ManyToMany
    private List<Guest> friends;

    public int getVisits() {
        return visits;
    }

    public void setVisits(int visits) {
        this.visits = visits;
    }

    public List<Guest> getFriends() {
        return friends;
    }

    public void setFriends(List<Guest> friends) {
        this.friends = friends;
    }
}

Hibernate：Forign键需要是主键

3 个答案: