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我已对此处列出的模型进行了必要的更改。但是，我不知道在我的连接表实体上放什么。

请注意，我的连接表有一个代理键和两个额外的列（日期和 varchar）。

到目前为止，我得到的是：

用户.java

@Entity
@Table (name = "tbl_bo_gui_user")
@DynamicInsert
@DynamicUpdate
public class User implements Serializable {
    private String id;
    private String ntName;
    private String email; 
    private Set<GroupUser> groupUsers = new HashSet<GroupUser>(0);

    // Constructors and some getters setters omitted

    @OneToMany(fetch = FetchType.LAZY, mappedBy = "pk.user", cascade=CascadeType.ALL)
    public Set<GroupUser> getGroupUsers() {
        return groupUsers;
    }

    public void setGroupUsers(Set<GroupUser> groupUsers) {
        this.groupUsers = groupUsers;
    }
}

组.java

@Entity
@Table (name = "tbl_bo_gui_group")
@DynamicInsert
@DynamicUpdate
public class Group implements Serializable {
    private String id;
    private String groupName;
    private String groupDesc;
    private Set<GroupUser> groupUsers = new HashSet<GroupUser>(0);

    // Constructors and some getters setters omitted

    @OneToMany(fetch = FetchType.LAZY, mappedBy = "pk.group", cascade=CascadeType.ALL)
    public Set<GroupUser> getGroupUsers() {
        return groupUsers;
    }

    public void setGroupUsers(Set<GroupUser> groupUsers) {
        this.groupUsers = groupUsers;
    }
}

问题是我不知道在我的连接表实体上放什么。这里是。

GroupUser.java

@Entity
@Table (name = "tbl_bo_gui_group_user")
@DynamicInsert
@DynamicUpdate
@AssociationOverrides({
    @AssociationOverride(name = "pk.user", 
            joinColumns = @JoinColumn(name = "id")),
    @AssociationOverride(name = "pk.group", 
            joinColumns = @JoinColumn(name = "id")) })
public class GroupUser implements Serializable {
    private String id;
    private User userId;
    private Group groupId;
    private Date dateCreated;
    private String createdBy;

    // constructors and getters and setters for each property

    // What now? ? No idea
}
4

1 回答 1

1

用户到组将是一种Many-To-Many关系。现在，您将其拆分为两个One-To-Many关系。因此，您的映射实体简单需要Many-To-Many通过使用来完成关系Many-To-One：

public class GroupUser implements Serializable {
    private String id;

    @ManyToOne
    private User userId;

    @ManyToOne
    private Group groupId;
    private Date dateCreated;
    private String createdBy;
}

另请参阅此示例：使用额外列映射多对多关联表（ 38 票赞成的答案）

于 2013-10-14T09:35:27.480 回答