orm.xml and many-to-many/join-table potential problem

dhartford · **Joined:** Fri Jul 30, 2004 4:02 pm **Posts:** 50

I'm attempting to implement a solution using only XML instead of annotations for JPA persistence.

Hibernate Entity Manager 3.3.1.ga

However, I've run into a snag where for an XML segment like this:

<many-to-many name="teachers" mapped-by="students" target-entity="Teachers" >
<join-table name="MYTEACHER_MYSTUDENT" >
<join-column name="TEACHER_ID"/>
<inverse-join-column name="STUDENT_ID"/>
</join-table>
</many-to-many>

The join table does not seem to be recognize - it throws something like this:

Code:

Dec 21, 2007 3:45:33 PM org.hibernate.util.JDBCExceptionReporter logExceptions
SEVERE: Invalid object name 'TEACHERS_STUDENTS'.

TEACHERS and STUDENTS are the respective table names of the entities, but defining my own join-table name 'MYTEACHER_MYSTUDENT' it ignores this. Creating a table to match what it wants partially corrects the problem, but I would like someone else with more experience to verify if this is a real problem or just my ignorance.

dhartford · **Joined:** Fri Jul 30, 2004 4:02 pm **Posts:** 50

And the followup is that the join-columns also seem to have problems (wanting something like teacher_id_TEACHERS and student_id_STUDENTS for column names instead of what was defined).

emmanuel · **Posted:** Sat Dec 22, 2007 5:31 am

it might be a small bug in the orm.xml parsing. Please open a JIRA issue with a minimal runnable test case.

dhartford · **Joined:** Fri Jul 30, 2004 4:02 pm **Posts:** 50

JIRA: http://opensource.atlassian.com/project ... se/ANN-687

dhartford · **Joined:** Fri Jul 30, 2004 4:02 pm **Posts:** 50

Is this handled in the Annotations jar -> o.h.cfg.annotations.reflections.EJB3OverriddenAnnotation.class?

I need this to work correctly to use the spec, so if you can help point me in the right direction I'll work on an internal patch so I can keep moving forward and publish any findings/corrections.

Code:

   private Columns buildColumns(Element element) {
      List<Element> subelements = element.elements( "column" );
      List<Column> columns = new ArrayList<Column>( subelements.size() );
      for (Element subelement : subelements) {
         columns.add( getColumn( subelement, false, element ) );
      }
      if ( columns.size() > 0 ) {
         AnnotationDescriptor columnsDescr = new AnnotationDescriptor( Columns.class );
         columnsDescr.setValue( "columns", columns.toArray( new Column[columns.size()] ) );
         return AnnotationFactory.create( columnsDescr );
      }
      else {
         return null;
      }
   }

dhartford · **Joined:** Fri Jul 30, 2004 4:02 pm **Posts:** 50

partial success with the column names not being respected.

If you use the attribute override tag to 'rename' the column, this tag is respected.

note that the column name I am 'overriding' is the same one that is expected by the relation mapping lookup. More testing to do from that other side if the attribute-override will work there or not.

Code:

        <id-class class="UserLocationsId"/>
        <!-- regular column names do not work, 
        so attribute-override (but before attributes elements) -->
        <attribute-override name="locationId">
            <column name="locations_LOCATION_ID"/>
        </attribute-override>    
        <attribute-override name="userId">
            <column name="useraccounts_USER_ID"/>
        </attribute-override>    
        
        <attributes>
            <id name="locationId">
                <column name="locations_LOCATION_ID"/>
            </id>
            <id name="userId">
                <column name="useraccounts_USER_ID"/>
            </id>
        </attributes>

emmanuel · **Posted:** Tue Feb 05, 2008 6:44 pm

Quote:

Is this handled in the Annotations jar -> o.h.cfg.annotations.reflections.EJB3OverriddenAnnotation.class?

Yes all the overriding strategy is there.