Hibernate version: 2.1.2
Database : DB2 v8.1

There is a one-to-one mapping between my two classes,SubFoo and Bar.
----------------------------
Mapping is:

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 2.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-2.0.dtd">
<hibernate-mapping>
<class name="Foo" table="foo">
<id column="ID" name="id" type="long">
<generator class="identity"></generator>
</id>
<subclass name="SubFoo" discriminator-value="subfoo">
<one-to-one name="bar" class="Bar" constrained="true" cascade="all"/>
</subclass>
</class>

<class name="Bar" table="Bar">
<id column="ID" name="id" type="long">
<generator class="foreign">
<param name="property">Bar</param>
</generator>
</class>

</hibernate-mapping>
--------------------------------
Related class :

Bar bar = new Bar();
SubFoo subfoo = new SubFoo();
subfoo.setBar(bar);
sess.save(subfoo);
---------------------------------------

While I'm persisting SubFoo bean, I take an exception as

HibernateException("unmapped property: " + propertyName); in net.sf.hibernate.persister.AbstractEntityPersister.

I looked at the example in Hibernate Users FAQ. But I couldn't solve the problem. Thanks for your interest.

Have you tried doing bar.setSubFoo(subfoo) before your .save()?

Bar class doesn't have a reference to SubFoo class. Only SubFoo has a reference to Bar. (Unidirectional) All I want is to save Bar and SubFoo classes by cascading Bar to SubFoo. But I'm unsuccesful. I solved the problem as:

Bar bar = new Bar();
SubFoo subfoo = new SubFoo();
subfoo.setBar(bar);
sess.save(subfoo);
subfoo=sess.refresh(subfoo);
sess.save(bar,subfoo.getId());

But this is not a good solution I think. If you know about the cascading save, I'll be appreciate for your answer.

have you tried

Bar bar = new Bar();
SubFoo subfoo = new SubFoo();
sess.save(subfoo);
subfoo.setBar(bar);
sess.save(bar);

oh no excuse


Bar bar = new Bar();
SubFoo subfoo = new SubFoo();
sess.save(bar );
subfoo.setBar(bar);
sess.save(subfoo);

Do you have to save the parent befor you add any children when the parent has an identity column and the children are all one-to-one with foriegn keys?

to conqueror:

I think the problem is with the lines:
<class name="Bar" table="Bar">
<id column="ID" name="id" type="long">
<generator class="foreign">
<param name="property">Bar</param>
</generator>
</class>

There is no property named Bar in the class Bar. Just move the lines:

<generator class="foreign">
<param name="property">Bar</param>
</generator>

to the SubFoo class declaration (since this is the right class that has the property) and everything should be OK.

And there is no need to perform save two times. Your example:

Bar bar = new Bar();
SubFoo subfoo = new SubFoo();
subfoo.setBar(bar);
sess.save(subfoo);

is OK.