Could not interpret type: Nullables.NHibernate.NullableInt32

gerrod · **Posted:** Tue Sep 20, 2005 11:03 pm

Hi all,

I've just started using nullables in NHibernate (rc1) in an ASP.NET application. Here's my mapping file:

Code:

<?xml version="1.0" encoding="utf-8" ?>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.0">
   <class name="Server.Objects.Event,NHibernateServer" table="Events">

      <id name="Id" column="EventID" type="Int32" unsaved-value="0" access="nosetter.lowercase">
         <generator class="native"/>
      </id>
      <property name="Name" />
      <property name="Description" />
      <property name="Start" />
      <property name="ArticleId" column="ArticleID" type="Nullables.NHibernate.NullableInt32Type, Nullables.NHibernate" />
   </class>
</hibernate-mapping>

However, when I try to hit my page, this exception gets thrown:

Code:

could not interpret type: Nullables.NHibernate.NullableInt32Type, Nullables.NHibernate
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: NHibernate.MappingException: could not interpret type: Nullables.NHibernate.NullableInt32Type, Nullables.NHibernate

To me, it sounds like NHibernate doesn't know where to look for the Nullables libraries; but I've added a reference to all the relevant libraries in all the relevant places. I've also searched around to try to find some help on the topic, but the match I found was in dutch, which was a bit hard to translate!

I'm hoping it's just an "it's 11 PM and it's time for bed" bug, but hopefully someone has an answer (or speaks dutch :-D).

Thanks!

bmichu · **Joined:** Thu Aug 11, 2005 4:21 am **Posts:** 2

Had the same problem.
Seems that with the previous version you could get by with just a reference to Nullables. I've added Nullable.NHibernate to the projects where this was not yet the case, and the problem is fixed.

xor · **Posted:** Wed Sep 21, 2005 8:21 am

No, this is not a bug. NHibernate by itself knows nothing about Nullables.NHibernate assembly. When you use nullables in your application by specifying type attribute, it creates dependence between your application and Nullables.NHibernate assembly, but not between NH and nullables. As soon as this is kind of "soft" dependence, not supported by compiler, you have to either manually copy necessary assemblies, or add a ordinal reference to your project.

gerrod · **Posted:** Wed Sep 21, 2005 5:19 pm

Thanks for the replies.

bmichu: Do you mean you just added a reference to your web project in Visual Studio, and the problem went away? My web project already has a reference to that library...

xor: Sorry, I meant it was probably a bug in MY code :oops:. I'd try copying the assemblies, but they're already in the BIN directory of both the web and server solutions.

sergey · **Posted:** Wed Sep 21, 2005 6:07 pm

The last time I've seen this happen was when I built NHContrib 0.8.4 release, and forgot to copy NHibernate 0.8.4 before building it, so NHC 0.8.4 used NH 0.8.3. But this time it must be something else, and I would really like to know what it is.

gerrod · **Posted:** Wed Sep 21, 2005 7:13 pm

I've managed to get it working. Basically I deleted every copy of:

that I could find in windows explorer, and that resided under the solution directory. Then I fired up VS, and removed all the references to said libraries, and recompiled just to watch it fail. Finally, I re-added the references back into all the relevant places, and now it all seems to be working happily.

So at the end of the day, I'm not sure what the problem was; my guess is that an old library of something was hanging around, but of course I have no idea which one or where.

*Curses Visual Studio's horrible handling of DLLs and versions*

Thanks everyone for the help and suggestions.