Inherited fluent nhibenate mapping issue
- by Aim Kai
I have an interesting issue today!! Basically I have two classes.
public class A : B
{
public virtual new ISet<DifferentItem> Items {get;set;}
}
public class B
{
public virtual int Id {get;set;}
public virtual ISet<Item> Items {get;set;}
}
The subclass A hides the base class B property, Items and replaces it with a new property with the same name and a different type.
The mappings for these classes are
public class AMapping : SubclassMap<A>
{
public AMapping()
{
HasMany(x=>x.Items)
.LazyLoad()
.AsSet();
}
}
public class BMapping : ClassMap<B>
{
public BMapping()
{
Id(x=>x.Id);
HasMany(x=>x.Items)
.LazyLoad()
.AsSet();
}
}
However when I run my unit test to check the mapping I get the following exception:
Tests the A mapping: NHibernate.PropertyAccessException : Invalid Cast (check your mapping for property type mismatches); setter of A
---- System.InvalidCastException : Unable to cast object of type 'NHibernate.Collection.Generic.PersistentGenericSet1[Item]' to type 'Iesi.Collections.Generic.ISet1[DifferentItem]'.
Anyone have any ideas?
Clearly it is something to do with the type of the collection on the sub-class. But I skimmed through the available options on the mapping class and nothing stood out as being the solution here.