I have a many-to-one relationship and not all of the values in the table are valid. When I retrieve a list of values Hibernate throws an UnresolvableObjectException with a nice message.

The problem is that I would like my app to provide the user the ability to fix the data, so I would like to override this behavior and return null for the field getter instead of blowing up when I retrieve the list.

There have been prior discussions about this, but none that I could find had a solution other then to not use hibernate to deal with the relationships with broken data. There’s even a JIRA request (HB-785), but it’s closed.

Has this been addressed?
Or does anyone have any ideas on how to work around it?

-peter

How is it possible ? - is it value in table or prepare data for saving.If you have corect design
(constraint rule) value in table can't invalid
I implement many-to-one with generic lov for user (use foreign key and many-to-one;
swing application) and hibernate work great
I check existance primary key, foreign key for new rows and search foreign keys for persistent row without problem
I don't use one-to-many

regards

There is not a constraint on the field, and you are correct - there should be and then it would never be a problem. I am mapping a legacy database and have to deal with the bad data provided.

-peter

It is problem - it depend from data

regards

That's correct. Unfortunatly I have to deal with bad data, which is beyond my control.
My hope was that there was a reasonable way for hibernate to deal with it.

Throwing an exception is perfect default behavior, as it's what you'd want 90% of the time.
My hope was that there was a way to override this behavior and do something like say return null for the many-to-one field.
That would give my application code an oppertunity to deal with it.

-peter

You can try set not-null="true" in many-to-one

not-null is not an attribute on many-to-one.
i also think it's just used in the schema exports.

You can set not-null in many-to-one - reference manual is old
I don't try with this field, but it is legal - middlegen add thi sattribute , too (in wrong place, but it isn't important)

regards

I have exactly the same problem, inconsistant data in the database. Did you manage to find a solution?

Only solution i can think of is it write some code into the POJO

I have a table which has a many-to-one and a one-to-many mapping to itslef. It is very much like the category table in the Hibernate in action book example.
this is my table info
name: Container
Column: ID (pk)
Column: name
Column: type
Columh: parentID(fk - which is refrencing the id column in this table)

this is not old database, i have designed it myself and basically it generates a 4 level down tree data.
This is my mapping xml.

<id name="id" type="long" unsaved-value="0" column="id">
<generator class="identity"/>
</id>
<property name="name"/>
<property name="type"/>

<many-to-one
name="parentContainer"
class="Container"
column="PARENTID"
cascade="none"/>

<set name="childContainers" inverse="true" cascade="all-delete-orphan">
<key column="PARENTID"/>
<one-to-many class="Container"/>
</set>

The problem i am having is when i create my first container it complains becuse technically it does not have a parent and it can't have a parent. the very fist level is the root. The parentId gets set to 0 for the top level containers but when reading it, i get exception saying no rows exist with id 0 which is a valid exception. but how can i avoid this? how can i resolve it?
one way that i had it work was to remove the association completely from the mapping and rely on old style queries by getting the children based on the id of the given container....any better idea? any solutions?
thanks.