I have some problems with the mapping of an association with classes that have proxy interface. I don't understand if i have to declare a collection of the interface type (es. ISet<IPerson>) or a collection of Concrete class (es Set<Person>) because i have problem in all the 2 ways... Could someone explain me how is the correct mapping of collection when the classes have a proxy interface specified?

Thanks
Daniele

1.2.0.0001 alpha 1



public abstract class GenericBO<IdT> : IGenericBO<IdT>
{
public IdT Id
{
get { return id; }
set { id = value; }
}

private IdT id = default(IdT);
}

public interface IGenericBO<IdT>
{
IdT Id { get; set; }
}


public class Appartamento : GenericBO<Int32>, IAppartamento
{
private String codice;
private String nome;
private ICollection<IFoto> foto;

public string Codice
{
get { return codice; }
set { codice = value; }
}

public string Nome
{
get { return nome; }
set { nome = value; }
}

public ICollection<IFoto> Foto
{
get { return foto; }
set { foto = value; }
}
}

public interface IAppartamento : IGenericBO<Int32>
{
string Codice { get; set; }

string Nome { get; set; }

ICollection<IFoto> Foto { get; set; }

}


public interface IFoto: IGenericBO<Int32>
{
string Path { get; set; }

IAppartamento Appartamento { get; set; }
}

public class Foto : GenericBO<Int32>, IFoto
{
private String path;
private IAppartamento appartamento;

public string Path
{
get { return path; }
set { path = value; }
}

public IAppartamento Appartamento
{
get { return appartamento; }
set { appartamento = value; }
}
}

<class name="Appartamento" table="Appartamenti" proxy="IAppartamento">
<id name="Id" column="Id" type="Int32">
<generator class="native"/>
</id>
<property name="Codice" column="Codice" type="String"></property>
<property name="Nome" column="Nome" type="String"></property>
<property name="Descrizione" column="Descrizione" type="String"></property>
<set name="Foto" lazy="true" inverse="true">
<key column="IdAppartamento" />
<one-to-many class="Foto"/>
</set>
</class>
<class name="Foto" table="Foto" proxy="IFoto">
<id name="Id" column="Id" type="Int32">
<generator class="native"/>
</id>
<property name="Path" column="Path" type="String"></property>
<many-to-one name="Appartamento" foreign-key="Id">
<column name="IdAppartamento"/>
</many-to-one>
</class>








MappingException: An association from the table Foto refers to an unmapped class: IAppartamento]
Daffini.DataAccess.NH.SessionManager.InitSessionFactory() in D:\Lavori\Progetti\Daffini.DataAccess\NHibernate\SessionManager.cs:65
Daffini.DataAccess.NH.SessionManager..ctor() in D:\Lavori\Progetti\Daffini.DataAccess\NHibernate\SessionManager.cs:27
Daffini.DataAccess.NH.Nested..cctor() in D:\Lavori\Progetti\Daffini.DataAccess\NHibernate\SessionManager.cs:39

[TypeInitializationException: The type initializer for 'Nested' threw an exception.]
Daffini.DataAccess.NH.SessionManager.get_Instance() in D:\Lavori\Progetti\Daffini.DataAccess\NHibernate\SessionManager.cs:19
Daffini.DataAccess.Web.SessionHttpModule.CommitAndCloseSession(Object sender, EventArgs e) in D:\Lavori\Progetti\Daffini.DataAccess\Web\SessionHttpModule.cs:59
System.Web.SyncEventExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +167
System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +117

Sql server express 2005

The collection itself must always by interface ( ISet<T>). And it seems that ISet<IFoto> mapping should work Ok.

But: You have problem in



As You do not define the association target class, NHibernate uses reflection to guess the type, it founds it to be IAppartamento which is unmapped. Add class attribute to fix it..

Gert

Thank you very much Gert.. you're kind..
you're suggest solve my problem.

If i write the code below always going well...

ICriteria criteria = session.CreateCriteria(typeof(Appartamento));
IList<IAppartamento> appartamenti = criteria.List<IAppartamento>();
appartamenti.GetEnumerator().MoveNext();
IAppartamento appartamento = appartamenti.GetEnumerator().Current;
Response.write(appartamento.Id);

But if i modify the code like this:

**new line**
ICriteria criteria = session.CreateCriteria(typeof(Foto));
IList<IFoto> appartamenti = criteria.List<IFoto>();
** **
ICriteria criteria = session.CreateCriteria(typeof(Appartamento));
IList<IAppartamento> appartamenti = criteria.List<IAppartamento>();
appartamenti.GetEnumerator().MoveNext();
IAppartamento appartamento = appartamenti.GetEnumerator().Current;
Response.write(appartamento.Id);

I received the following error:

System.ArgumentException: Cannot resolve method Int32 get_Id() because the declaring type of the method handle Daffini.DataAccess.Domain.IGenericBO`1[IdT] is generic. Explicitly provide the declaring type to GetMethodFromHandle.

[ArgumentException: Cannot resolve method Int32 get_Id() because the declaring type of the method handle Daffini.DataAccess.Domain.IGenericBO`1[IdT] is generic. Explicitly provide the declaring type to GetMethodFromHandle. ]
System.Reflection.MethodBase.GetMethodFromHandle(RuntimeMethodHandle handle) +2335793
ProxyInterfaceSystemObject_IAppartamento_INHibernateProxy_ISerializable.get_Id() +58

[TargetInvocationException: Property accessor 'Id' on object 'ProxyInterfaceSystemObject_IAppartamento_INHibernateProxy_ISerializable' threw the following exception:'Cannot resolve method Int32 get_Id() because the declaring type of the method handle Daffini.DataAccess.Domain.IGenericBO`1[IdT] is generic. Explicitly provide the declaring type to GetMethodFromHandle. ']
System.ComponentModel.ReflectPropertyDescriptor.GetValue(Object component) +499
System.Web.UI.DataBinder.GetPropertyValue(Object container, String propName) +186
System.Web.UI.DataBinder.Eval(Object container, String[] expressionParts) +120
System.Web.UI.DataBinder.Eval(Object container, String expression) +173
ASP.listapartments_aspx.__DataBind__control4(Object sender, EventArgs e) in d:\Lavori\Progetti\Natalia\Appartamenti-Kiev\ListApartments.aspx:23
System.Web.UI.Control.OnDataBinding(EventArgs e) +88
System.Web.UI.Control.DataBind(Boolean raiseOnDataBinding) +167
System.Web.UI.Control.DataBind() +31
System.Web.UI.Control.DataBindChildren() +236
System.Web.UI.Control.DataBind(Boolean raiseOnDataBinding) +178
System.Web.UI.Control.DataBind() +31
System.Web.UI.WebControls.Repeater.CreateItem(Int32 itemIndex, ListItemType itemType, Boolean dataBind, Object dataItem) +160
System.Web.UI.WebControls.Repeater.CreateControlHierarchy(Boolean useDataSource) +539
System.Web.UI.WebControls.Repeater.OnDataBinding(EventArgs e) +72
System.Web.UI.WebControls.Repeater.DataBind() +86
ListApartments.set_Appartamenti(IList`1 value) in d:\Lavori\Progetti\Natalia\Appartamenti-Kiev\ListApartments.aspx.cs:36
Daffini.AppartamentiKiev.Presentation.Presenter.ListApartmentsPresenter.Initialize() in D:\Lavori\Progetti\Natalia\Daffini.AppartamentiKiev.Presentation\Presenter\ListApartmentsPresenter.cs:25
ListApartments.Page_Load(Object sender, EventArgs e) in d:\Lavori\Progetti\Natalia\Appartamenti-Kiev\ListApartments.aspx.cs:16
System.Web.Util.CalliHelper.EventArgFunctionCaller(IntPtr fp, Object o, Object t, EventArgs e) +31
System.Web.Util.CalliEventHandlerDelegateProxy.Callback(Object sender, EventArgs e) +68
System.Web.UI.Control.OnLoad(EventArgs e) +88
System.Web.UI.Control.LoadRecursive() +74
System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +3036



The problem is only on the "ID" property. If I read all the other property except ID all going well..

Sounds like the Castle.DynamicProxy is not handling generic interfaces correctly.. And, with quick search,
http://forum.castleproject.org/viewtopic.php?t=866&highlight=generic

So, You propably must give up lazy loading (== remove "proxy" attributes from mapping), or remove the IGenericBO<IdT> interface.

EDIT: After a second thought, if You might be able to get this fixed by DynamicProxy team - after all, the IAppartemento interface is not generic any more...

Gert

Ok, thanks again.. i don't happy of this.. but it seems to work... :-)
If i understand, is a limit of Castle.DinamicProxy?

And another question.. i want to write a generici Equals method, and i write in the GenericBO classes a method like this..

public override bool Equals(object obj)
{
if (obj == null || GetType() != obj.GetType())
{
return false;
}

return ((IGenericBO<IdT>) obj).Id.Equals(Id);
}

With lazy loading this test is always false because if the object come from a collection it's type is ProxyInterfaceSystemObject_IAppartamento_INHibernateProxy_ISerializable

There is a way to code a general Equals method for all my business object?

I do not know DynamicProxy well enought to tell. It might be problem in how NHibernate uses DynamicProxy...



I do not have good ideas... Maybe someone else?

Gert

The only solution that i found is this.. http://cs.nerdbank.net/blogs/jmpinline/ ... 4/126.aspx

But i have to implement a similar Equals method in all my business object...

I finally the solve the problem with a code like this :

public override bool Equals(object obj)
{
if (obj == this) return true;

obj = getImplementation(obj);
if (obj.GetType() != GetType() ) return false;
return Id.Equals(((GenericBO<IdT>) obj).Id);

}

protected object getImplementation(object obj)
{
if (obj is INHibernateProxy)
{
return NHibernateProxyHelper.GetLazyInitializer((INHibernateProxy) obj).GetImplementation();
}
else
{
return obj;
}
}

I've before tryed to use
public override bool Equals(object obj)
{
if (obj == this) return true;

NHibernate.NHibernateUtil.Initialize(obj);
if (obj.GetType() != GetType() ) return false;
return Id.Equals(((GenericBO<IdT>) obj).Id);

}

but it doesn't work...