I've been trying to use Hibernate to set up ORM for a member class (i.e. a class nested inside another class). But it doesn't seem to work. An example config is shown below. Does anyone know if Hibernate actually supports member classes?

For the class name in the HBM, I've tried using both "com.example.ParentClass$MemberClass" and "com.example.ParentClass.MemberClass".

The first gives class name gives the following exception:



The second gives:




Am I doing something wrong?


Hibernate version:
Hibernate3 (via Spring)

Mapping documents:



[b] Java class




Thanks!

I executed the same example with hibernate 3.2 version. And it works without any error message.

Here is the mapping I used :

<hibernate-mapping>
<class name="bean.Parent$Member" table="Member">
<id name="id"></id>
<property name="prop"></property>
</class>
</hibernate-mapping>

Here is the Parent Class :

public class Parent
{
class Member
{
private int id;
private int prop;

Member()
{
}
public int getId()
{
return id;
}
public void setId(int id)
{
this.id = id;
}
public int getProp()
{
return prop;
}
public void setProp(int prop)
{
this.prop = prop;
}
}
}

Probably try to declare Member() constructor as public.

Thanks waswani... I tried this but it made no difference. However, note that I don't get the exception until I actually try to use the MemberClass object. In this case, I am using it as the return object in a named query.

I'm not sure what else to do. I tried moving the member class outside of the parent class into a normal class, and everything works great.

As per Basic Java Concept, to create a inner class object , you should first create the Parent object.

I think Hibernate can not judge from the mapping that it is a Inner class and hence throws the error while instantiating the object.

If you decalre the inner class as static, it should work but I don't know if making the class static would solve your business.

Thanks waswani. That's an interesting point about instantiating a member class outside of its parent class. I guess I'm not sure how Hibernate would accomplish this in practice.

So it would seem to me that ORM may not actually work for member classes. Something to ponder, I suppose.