Question

This question is in follow up to this post Grails one to many relationship view

The example suggested there is not working and throwing following exception at run time

null id in blog.omarello.Phone entry (don't flush the Session after an exception occurs). Stacktrace follows:
Message: null id in blog.omarello.Phone entry (don't flush the Session after an exception occurs)
   Line | Method
->>  43 | doCall  in blog.omarello.ContactController$_closure4$$ENLORkU6
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 
|   886 | runTask in java.util.concurrent.ThreadPoolExecutor$Worker
|   908 | run . . in     ''
^   662 | run     in java.lang.Thread

I think rather then making the example work can any one help me understand how can I create a GSP which can let me save multiple instances of same domain class. For example, a GSP which can let me insert multiple Book instances at once?

Answer 1

Change the Contact class in the phone example as follows and it should work fine.

package blog.omarello

import org.apache.commons.collections.list.LazyList;
import org.apache.commons.collections.FactoryUtils;

class Contact {

    static constraints = {
        firstName(blank:false)
        lastName(blank:false)
    }

    String firstName
    String lastName
    String nickName


 List phones = LazyList.decorate(new ArrayList(),
                                  FactoryUtils.instantiateFactory(Phone.class));


//    List phones = new ArrayList()
    static hasMany = [ phones:Phone ]

    static mapping = {
        phones cascade:"all-delete-orphan"
    }

//    def getPhonesList() {
//        return LazyList.decorate(
//              phones,
//              FactoryUtils.instantiateFactory(Phone.class))
//    }

    def String toString() {
        return "${lastName}, ${firstName}"
    }
}