Spring Rest Hibernate OneToMany / ManyToOne

Question

我尝试使用用户名作为外键创建具有OneToMany关系的用户表，但ManyToOne关系中的用户名字段每次都是Null。

关系：

User:

    @OneToMany(targetEntity = Authority.class, cascade=CascadeType.ALL, mappedBy="username")
    private Collection<Authority> authorities

Authority:

    @Column(nullable = false, name="username")
    @JoinColumn(name="user_username")
    String username;

结果表：

+----+--------------------+-----------+---------+
| id | username           | password  | enabled |
+----+--------------------+-----------+---------+
| 13 | will               | q         |       0 |
| 34 | I just got editted | adufhasdf |       1 |
| 36 | wakakawakwakaak    | ballz     |       0 |
+----+--------------------+-----------+---------+

+----+----------+------------+
| id | username | authority  |
+----+----------+------------+
|  6 | NULL     | ROLE_ADMIN |
|  7 | NULL     | ROLE_ADMIN |
|  8 | NULL     | ROLE_ADMIN |
| 12 | NULL     | ROLE_BASIC |
| 13 | NULL     | ROLE_BASIC |
| 14 | NULL     | ROLE_BASIC |
| 17 | NULL     | ROLE_BASIC |
| 18 | NULL     | ROLE_BASIC |
| 19 | NULL     | ROLE_BASIC |
| 20 | NULL     | ROLE_BASIC |
| 21 | NULL     | ROLE_BASIC |
| 22 | NULL     | none       |
| 23 | NULL     | ROLE_BASIC |
| 24 | NULL     | ROLE_BASIC |
| 25 | NULL     | none       |
| 26 | NULL     | none       |
| 27 | NULL     | ROLE_BASIC |
| 28 | NULL     | none       |
| 29 | NULL     | ROLE_ADMIN |
| 30 | NULL     | ROLE_ADMIN |
| 31 | NULL     | ROLE_BASIC |
| 39 | NULL     | ROLE_BASIC |
| 40 | NULL     | ROLE_USER  |
| 41 | NULL     | ROLE_USER  |
| 42 | NULL     | ROLE_USER  |
| 43 | NULL     | ROLE_ADMIN |
| 44 | NULL     | ROLE_ADMIN |
| 45 | NULL     | ROLE_USER  |
+----+----------+------------+

Answer 1

您的JoinColumn应该是：

@JoinColumn(name="username")

这是因为该字段在username实体中被标识为Authority。

Answer 2

我认为原因是多方面的，你必须使用User对象而不是String。这是我尝试过的，它有效。

//用户

@OneToMany(targetEntity = Authority.class, fetch = FetchType.EAGER, mappedBy = "user")
private Collection<Authority> authorities;

//管理局

@ManyToOne
@JoinColumn(name="username", referencedColumnName = "username")
private User user;

结果：

希望这有帮助！

Answer 3

JPA文档中出现了一个简单的答案。

在用户

中

@OneToMany(targetEntity = Authority.class , cascade = CascadeType.ALL)
@JoinColumn(name="username", referencedColumnName="username")
private List<Authority> authorities

然后是管理局

@Column(nullable = false)
String username;