Question

I have a structure with the following domain classes:

class Service{ static hasMany=[serviceRequirements:ServiceRequirement]}

And of course a bunch of member variables…
Problem occurs when I’m trying to set the properties in the controller like this:

service.properties = params

I get the following error:

Executing action [update] of controller [se.hb.eme.DeveloperController] caused exception: Invalid property 'serviceRequirements[0]' of bean class [se.hb.eme.Service]: Index of out of bounds in property path 'serviceRequirements[0]'; nested exception is java.lang.IndexOutOfBoundsException: Index: 0, Size: 0

There’s pretty much no documentation on grails.org about this and I really can’t figure out the problem…

The .gsp is pretty simple. (I removed some fields…)

<g:form action="create">
<g:textField name="header" />
<g:textField name="serviceRequirements[0].header" /> 
<g:submitButton value="Create" />

Answer 1

If I understand it correctly that’s because the code is trying to set element 0 of a list, which has no elements in it, thus throwing an index out of bounds exception.

Try this in your domain class:

class Service{
  List<ServiceRequirement> serviceRequirements = ListUtils.lazyList(new ArrayList(), {new ServiceRequirement()} as org.apache.commons.collections.Factory)
  static hasMany = [serviceRequirements:ServiceRequirement]
}