I'm having a similar problem to this post. although the component approach does not seem to work.

I have two classes: PropertyReportOrder and PropertyReport. They have a bidirectional one-to-one relationship, and both must be mapped to the property_report table.

If I map one as a component, then it doesn't seem that I would be able to access the other one directly, which I will need to be able to do. At some times, users will want to start with a PropertyReport and see its PropertyReportOrder, and at other times they will need to start with the order and then get to the report.

I thought about doing separate class/component mappings for BOTH classes, but it seems a little weird. Also, that solution breaks for PropertyReport because it needs to have mapped subclasses, and <component> does not allow <joined-subclass> nodes. (and that's another problem -- described in this posting.)

So far the only thing I can get to work is to use <many-to-one> mappings between the two classes.

Components have no life out of their master entity, then component is not what you want.


<parent> tag of component might help.


I can't follow you. Why not having a bidirectional 1-to-1 mapping between PropertyReport (entity) and PropertyReportOrder (entity) wo component at all ?

Yes a 1-1 mapping would be ideal, except that Hibernate does not appear to allow a one-to-one mapping when both entities come from the same table. I get a class cast exception from Hibernate.

I've read other threads that say that the obvious solution when people need a 1-1 on the same table is to use component, but it does not seem appropriate here, and it will not work if my component needs to have subclasses.

So I've been using many-to-one, which also seems inappropriate.

actually, you could use a custom persister to do this. Just override getIdentifierSpace() to return something other than the tablename.

That was easy! I just had getIdentifierSpace() return the class name. Works great.