use*_*198 5 java grails entity-relationship grails-orm relationship
我有以下两个域类,用户和帖子我和他们之间有两个关系,用户有一对多的帖子有后引用.用户与他所关注的帖子有多对多的关系:我得到的关系如下:
User {
hasMany = [posts : Post, followingPosts: Post]
belongsTo = [Post] //For the many-to-many, this is the owner i'd like to have.
}
Post {
hasMany = [followers: User]
belongsTo = [owner: User] //For the 1-to-Many, this is my back-reference
}
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现在我和Grails发生了冲突,我尝试通过映射解决它,但没有成功,这是我得到的错误:
Domain classes [Post] and [User] cannot own each other in a many-to-many relationship. Both contain belongsTo definitions that reference each other. (Use --stacktrace to see the full trace)
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有谁知道如何解决这个问题?
我认为你可以使用mappedBy来做到这一点,例如:
class User{
static hasMany = [posts : Post, followingPosts: Post]
static mappedBy = [posts : "user"]
}
class Post{
User user
static hasMany = [followers: User]
static belongsTo = User
}
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查看此内容以获取有关mappedBy的更多信息。
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