Java 一对一外键

我的项目中的一对一外键关系映射有问题

User.java

@Access(AccessType.FIELD)
@Entity
@Table(name = "users")
public class User {
public Role ro;

@Id
@GeneratedValue(strategy = GenerationType.AUTO)
public int user_id;
@Column(name = "username")
public String username;
@Column(name = "password")
public String password;


@OneToOne(cascade = CascadeType.ALL)
@JoinColumn(name = "username")
public Role getRo() {
    return ro;
}

public void setRo(Role ro) {
    this.ro = ro;
}

@Column(name = "enabled")

public int enabled;


public User() {
}

public int getUser_id() {
    return user_id;
}

public User(String username, String password, int enabled) {
    this.username = username;
    this.password = password;
    this.enabled = enabled;

}


public String getUsername() {
    return username;
}

public void setUsername(String username) {
    this.username = username;
}

public String getPassword() {
    return password;
}

public void setPassword(String password) {
    this.password = password;
}

public int getEnabled() {
    return enabled;
}

public void setEnabled(int enabled) {
    this.enabled = enabled;
}



@Override
public String toString() {
    return String.format(
            "student[id=%d, name='%s', age='%d']",
            ro.getUsername(), username, ro.getUsername());
}

}

Role.java

import javax.persistence.*;

@Access(AccessType.FIELD)
@Entity
@Table(name = "user_roles")
public class Role {

@Id
@GeneratedValue(strategy = GenerationType.AUTO)
public int user_role_id;
@Column(name = "username")
public String username;
@Column(name = "role")
public String role;

public User user;


@OneToOne(mappedBy = "ro")
public User getUser() {
    return user;
}

public void setUser(User user) {
    this.user = user;
}



public Role(String username, String role) {
    this.username = username;
    this.role = role;
}

public Role() {
}

public int getUser_role_id() {
    return user_role_id;
}



public String getUsername() {
    return username;
}

public void setUsername(String username) {
    this.username = username;
}

public String getRole() {
    return role;
}

public void setRole(String role) {
    this.role = role;
}



}

这就是错误：

原因：org.hibernate.MappingException:无法确定以下列的类型：com.company.project.models.Role，在表：users中：[org.hibernate.mapping.Column（ro）] 在org.hibernate.mapping.SimpleValue.getType（SimpleValue.java:431）~[hibernate-core-5.0.12.Final.jar:5.0.12.Final] 在org.hibernate.mapping.SimpleValue.isValid（SimpleValue.java:398）~[hibernate-core-5.0.12.Final.jar:5.0.12.Final] 在org.hibernate.mapping.Property.isValid（Property.java:225）~[hibernate-core-5.0.12.Final.jar:5.0.12.Final] 在org.hibernate.mapping.PersistentClass.validate（PersistentClass.java:595）~[hibernate-core-5.0.12.Final.jar:5.0.12.Final] 在org.hibernate.mapping.RootClass.validate（RootClass.java:265）~[hibernate-core-5.0.12.Final.jar:5.0.12.Final] 在org.hibernate.boot.internal.MetadataImpl.validate（MetadataImpl.java:329）~[hibernate-core-5.0.12.Final.jar:5.0.12.Final] 在org.hibernate.boot.internal.SessionFactoryBuilderImpl.build（SessionFactoryBuilderImpl.java:443）~[hibernate-core-5.0.12.Final.jar:5.0.12.Final] 在org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.build（EntityManagerFactoryBuilderImpl.java:879）~[hibernate-entitymanager-5.0.12.Final.jar:5.0.12.Final]

---

... 22省略的公共帧

您应该在变量声明或getter（）上注释所有

@Column

/

@OneToOne

。这就是为什么hibernate在

类用户中找不到
角色
请尝试在变量或用户
类
中的getter上注释所有
@列
和
@MappedBy
。谢谢，我现在没有为实体指定标识符：com.company.project.models.User。这是我的代码@Id@GeneratedValue（strategy=GenerationType.AUTO）public int getUser_Id（）{return user_Id；}您确定不能混合使用字段注释和方法注释吗？我同意这样做是不好的做法。我确信你不能为
@Column
注释这样做，也不能完全确定映射。的确是坏习惯。谢谢