I am working with a legacy database that uses composite keys. I created a composite identifier class, OperationId, to use as the id for my Operation class. In OperationId, I implement ISerializable and override Equals and GetHashCode. My Operation.hbm.xml class (compiled as an embedded resource) is:

<?xml version="1.0" encoding="utf-8" ?>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.0">
<class name="ClassTester.Operation, ClassTester" table="OPERTN_NM_REF">
<composite-id name="Id" class="ClassTester.OperationId">
<key-property name="OperationCode" column="OPERTN_CD" />
<key-property name="OperationCategory" column="OPERTN_CAT_REF_CD" />
</composite-id>
<property name="DeleteIndicator" column="DLT_IND" type="Char" length="1"/>
<property name="OperationName" column="OPERTN_NM" type="String" length="50" />
<property name="OperationMessage" column="OPERTN_MSG_TXT" type="String" length="100" />
<property name="OperationDescription" column="OPERTN_DSC_TXT" type="String" length="200" />
</class>
</hibernate-mapping>

I have verified that the OperationId class is in my assembly (ClassTester).

When I execute
cfg.AddAssembly( "ClassTester" );
--OR--
cfg.AddClass( typeof( Operation ) );

I get the following exception:
Unhandled Exception: NHibernate.MappingException: component class not found --->
System.TypeLoadException: Could not load type ClassTester.OperationId
from assembly NHibernate, Version=0.8.3.0, Culture=neutral, PublicKeyToken=154fdcb44c4484fc.
at System.Type.GetType(String typeName, Boolean throwOnError)

at NHibernate.Cfg.Binder.BindComponent(XmlNode node, Component model,
Type reflectedClass, String className, String path, Boolean isNullable, Mappings mappings)


The way I read the exception, NHibernate is looking in the NHibernate assembly for my class instead of in my assembly

Where am I going wrong?

Thanks,
Chris

You have to use fully qualified name, just as you did in <class name="...">. By the way, if you specify assembly and namespace in the <hibernate-mapping> element, you won't need to qualify the class names in the mapping.

Thank you for the quick reply, Sergey.

I tried:
cfg.AddClass( typeof( ClassTester.Operation ) );

and got the same result. Is this what you meant?

Sorry, I meant you have to use fully qualified name in the mapping, in the <composite-id> tag.

Here is my <composite-id> tag:
<composite-id name="Id" class="ClassTester.OperationId">
<key-property name="OperationCode" column="OPERTN_CD" />
<key-property name="OperationCategory" column="OPERTN_CAT_REF_CD" />
</composite-id>

The class attribute is fully qualified. Am I missing an attribute or element?

No, you're missing the assembly name in the class attribute. It should be class="ClassTester.OperationId, ClassTester". If there's no assembly, .NET assumes the executing assembly which is NHibernate.dll, that's why it attempts to load the type from there.

Thank you, Sergey. Now I'm rolling.