GORM delete operation : Found two representations of same collection

@Entity
public class Contact{
    List associations

    static hasMany[
    associations:Contact
    ]

    static mapping[
    associations cascade:"all-delete-orphan"
    ]
}

and i have service for deleting associations from Contact entity like this

Contact.withTransaction{status ->
        user.contacts.collect{Contact c->
            c.associations.collect{Contact association->
  开发者_如何学JAVA              c.associations.remove(association)
            }
        }
     }

when trying this i get org.hibernate.HibernateException:Found two representations of same collection: Contact.associations

do i making a mistake or any other way to delete associations from Contact?

first of all you should not use collect in this case. i think the appropriate method would be each. you don't need to use a withTransaction at this point, expecting you would use a new hibernate session. try this:

def assocs = []
// store collection to avoid concurrent modification exception by during delection with in each   method
assocs += user.contacts.associations
assocs.each {
   // because of your cascase setting all orphans will be deleted automatically
   user.contacts.removeFromAssociations(it)
}

I think there's a shorter way to do the task:

def contact = Contact.get(...) // retrieve a contact
contact.associations.clear() // remove all associations of the contact

If you are not familiar with GORM, it's better to start with this blog post.

I solved the problem. Problem was because of deleting the associations that in array. When i getting contact list it also give me associations because associations are also instance of contact. So firstly, i get the contact list with sql query by getting only contacts then i deleted the associations of contacts. Much Thanks to everyone especially to Hoàng Long :)