两个外键作为主键 [英] Two foreign keys as primary key

问题描述

如何使用休眠注释实现以下表格?

How would I implement the following tables using hibernate annotations?

当前代码为:(为简洁起见)

用户

@Entity
@Table(name = "user")
public class User implements java.io.Serializable {
    @Id
    @GeneratedValue
    public Long getId() {
        return id;
    }
}

社交网络

@Entity
@Table(name = "social_network")
public class SocialNetwork implements java.io.Serializable {
    @Id
    @GeneratedValue
    public int getId() {
        return id;
    }
}

SocialProfile

@Entity
@Table(name = "social_profile")
public class SocialProfile implements java.io.Serializable {
    @Id
    @ManyToOne
    @JoinColumn(name="user_id")
    public User getUser() {
        return user;
    }

    @Id
    @ManyToOne
    @JoinColumn(name="social_network_id")
    public SocialNetwork getSocialNetwork() {
        return socialNetwork;
    }
}

很明显，我的代码目前无法正常工作.任何人都可以对此有所了解吗?

Obviously my code is not working correctly right now. Can anyone shed some light onto this?

推荐答案

您需要这样的可嵌入的SocialProfileId:

you need an embeddable SocialProfileId like this :

@Embeddable
public class SocialProfileId implements Serializable {
    @Column(name = "user_id")
    private long userId;
    @Column(name = "social_network_id")
    private long socialNetworkId;
}

然后，您的SocialProfile实体将如下所示:

then, your SocialProfile entity will look like this :

@Entity
@Table(name = "social_profile")
public class SocialProfile implements java.io.Serializable {

    @EmbeddedId
    private SocialProfileId id;

    @ManyToOne
    @JoinColumn(name="user_id")
    public User getUser() {
        return user;
    }

    @ManyToOne
    @JoinColumn(name="social_network_id")
    public SocialNetwork getSocialNetwork() {
        return socialNetwork;
    }
}

编辑抱歉，我在答案中的字段和方法上使用了混合注释...绝对不要这样做！ ;-)

EDIT sorry, i have mixed annotations on fields and methods on my answer ... never do that ! ;-)

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