在两个域对象上一对一地学习

Question

I want to add a child to two different parent class, like that:

First:

class Member {
    Profile profile

    Member() {
        this.profile = new Profile()
    }

    static mapping = {
        profile cascade: 'all-delete-orphan'
    }
}

Second:

class Team {
    Profile profile

    Team() {
        this.profile = new Profile()
    }

    static mapping = {
        profile cascade: 'all-delete-orphan'
    }
}

Thw child is simply define like that

  class Profile() {
  }

The probleme is when I save the parent, it dosent save the child:

Member member = new Member().save(flush: true, failOnError: true)

assert !member.hasErrors()
assert member.profile           
assert !member.profile.hasErrors()

assert member.profile.id //FAIL

What do I do wrong? Is there a better way to do it?

UPDATE:

I found this

Saving associated domain classes in Grails

It seem that 'belong to' is needed for that kind of behavior. But Why the 'cascade: 'all-delete-orphan' doesn't force this ? Because I can't use 'belong to' in that specific case

Answer 1

I copied your example (with slight modification to change group table name to a non-reserved word) and the cascades are working properly using grails 2.2.1. Both Member and Group cascaded their saves to the newly created Profiles .

Assuming your classes are more complicated than this, you might have an error elsewhere in your class (eg cascade behavior described in constraints instead of mapping , etc).

Answer 2

I found a nice solution. The best was to define both parent in the child but nullable. Like that:

class Profile() {
    static belongsTo = [member: Member, team: Team]

    static constraints = {
        member nullable: true
        team nullable: true
    }
}

This way, the cascade behavior work just fine !