Hi,

We have a existing object design that I am trying to map in Hibernate. Here is the jist.

Class Buyer is an Interface, and one implementing class is BuyerData:

<class name="data.partnership.Buyer" table="BUYER_SETUP">

<id column="BUYER_ID" name="id" type="java.lang.Long" unsaved-value="null">
<generator class="util.hibernate.SequenceIntervalGenerator">
<param name="sequence">SEQ_BUYER_ID</param>
<param name="interval">1</param>
</generator>
</id>

<subclass name="com.notiva.cbo.buyer.data.partnership.BuyerData">

<property column="BUYER_COLLAB_UID_TXT" name="buyerUid" type="java.lang.String"/>
....
</subclass>
</class>

We have another class that needs to return the Interface:

<class name="data.partnership.SellerPartnershipData" table="SELLER_PARTNERSHIP_SETUP">

<id column="SELLER_PARTNERSHIP_ID" name="id" type="java.lang.Long" unsaved-value="null">
<generator class="com.notiva.util.hibernate.SequenceIntervalGenerator">
<param name="sequence">SEQ_SELLER_PARTNERSHIP_ID</param>
<param name="interval">1</param>
</generator>
</id>

<property column="BUYER_ID" name="buyer" type="data.partnership.Buyer"/>
...
</class>

This is the Java file:

public class SellerPartnershipData extends AbstractSeller
implements Partnership, Effective {

public Buyer getBuyer() {
return null;
}
....
}



But during startup, the hibernate session factory errors out on the latter mapping file with this error:

13:37:13,968 ERROR [Configuration] Could not compile the mapping document
net.sf.hibernate.MappingException: Could not interpret type: com.notiva.core.data.partnership.BuyerData

Any ideas? thanks.

Matt

How are com.notiva.cbo.buyer.data.partnership.BuyerData and com.notiva.core.data.partnership.BuyerData related?

Well, I truncated the package names for readability, but here they are fully qualified:

com.notiva.cbo.buyer.data.partnership.BuyerData

implements

com.notiva.core.data.partnership.Buyer


...and this class:

com.notiva.cbo.buyer.data.partnership.SellerPartnershipData

has this method:

public Buyer getBuyer() {
return null;
}



I just want to be able to return an Interface in the mapping. Thanks.

Matt

I think for a class type to be mentioned as a many-to-one type, that class also has to be a Hibernate mapped class. So somewhere you'd have to have


and have com.notiva.cbo.buyer.data.partnership.BuyerData and other implementing classes as <subclass>s of that class.

I thought I did that.

oh sorry, I got confused with your truncated class names. then I'm not sure what's going on

I think I might have figured out what my problem is. Our interface (Buyer) is really the only subclass, so there is no discriminator value (dont ask why it is only subclass). So if I strip id down to just trying to load that mapping, I get:



..so I think my only solution is to add a default discriminator column, or not use the interface.

matt

Looks like you don't need to map the interface at all. You -do- realise that the declared type of the property does -not- need to match the type declared in the <many-to-one> element, right?

Here's my penance:

Instead of <many-to-ones.. we have used <properties and it seems to have worked in the past, but it did not work in this case. Maybe the <property tag has stronger inspection and didn't like the subclass, whatever... but when we used the (proper) <many-to-one it worked.

Thanks,

Matt