NHibernate DuplicateMappingException when two classes have the same name but different namespaces

Question

I have a class in my domain model root that looks like this:

namespace Domain
{
  public class Foo { ... }
}

I also have another class with the same name in a different namespace:

namespace Domain.SubDomain
{
  public class Foo { ... }
}

For my mappings, I have a Mapping directory with a subdirectory called SubDomain that contains mappings for the domain classes found in Domain.SubDomain namespace. They are all in the same assembly.

However, when I try to load them with NHibernate, I keep getting a DuplicateMappingException... even though both Foos having different namespaces. The code I am using to load my NHibernate configuration is this:

var cfg = new Configuration()
  .Configure()                
  .AddAssembly("Domain");   

How can I tell NHibernate to let me use two entities with the same name (but different namespaces)?

Answer 1

I found the answer on the Hibernate website:

If you have two persistent classes with the same unqualified name, you should set auto-import="false". An exception will result if you attempt to assign two classes to the same "imported" name.

I used that as an attribute for the <hibernate-mapping> tag and it worked.

Answer 2

I have had the same problem. I solved it like this:

Fluently.Configure()
            .Database(MsSqlConfiguration.MsSql2008
                .ConnectionString(...)
                .AdoNetBatchSize(500))
            .Mappings(m => m.FluentMappings
                .Conventions.Setup(x => x.Add(AutoImport.Never()))
                .AddFromAssembly(...)
                .AddFromAssembly(...)
                .AddFromAssembly(...)
                .AddFromAssembly(...))
            ;

The imported part is: .Conventions.Setup(x => x.Add(AutoImport.Never())). Everything seems to be working fine with this configuration.

Answer 3

You can specify a classes fully qualified name in the mapping document like so:

<class name="SeeMe.Data.People.Relationship, SeeMe.Data" ... > ...

Where SeeMe.Data is the assembly.