Hibernate"ManyToOne ...引用未知实体"异常

Question

我只是无法使用Hibernate将我的两个类映射到SQL表之间的关系.

角色类:

@Entity
@Table(name = "role")
public class Role {
    @Id 
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name="id")
    private int id;

    @Column(name="name")
    private String name;

    @OneToMany(mappedBy="memberinfo")
    private Set<Memberinfo> members;

    ...
}

和Memberinfo类:

@Entity
@Table(name = "memberinfo")
public class Memberinfo {

    @Id @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name="id", nullable = false)
    private int id;

    @Column(name = "userid", nullable = false)
    private String userid;

    @Column(name = "email", nullable = false)
    private String email;

    @Column(name = "password", nullable = false)
    private String password;

    @Column(name = "salt", nullable = false)
    private String salt;

    @Column(name = "name", nullable = false)
    private String name;

    @Column(name = "address")
    private String address;

    @Column(name = "phonenum")
    private String phonenum;

    @ManyToOne(targetEntity=Role.class)
    @JoinColumn(name="role_id")
    private Role role;

    ...
}

当我尝试从数据库中获取数据时,它会连接,但会引发异常:"HTTP状态500 - 模型上的@OneToOne或@ManyToOne.Memberinfo.role引用未知实体:model.Role".

如果我删除变量"Role",那么它可以工作,我可以获取成员资格数据,但我需要两个表之间的连接,但在这种情况下,每次都会出现前面提到的异常.

到目前为止,stackoverflow上没有其他解决方案对我有用.

知道我做错了什么吗？

Answer 1

如果类实际上不是实体(未注释whith javax.persistence @Entity)或者persitence提供者不"知道"类(包未扫描),则可以抛出"未知实体错误".

在Memberinfo中导入的Role类是正确的吗？也许您正在从另一个库导入另一个Role类.