Order of delete in unit of work

Question

Hi,
I'm trying to delete two objects, a beamprocess and a beamprocessType, where the beamprocess has a 1-1 relationship with the beamprocessType. This means of course that the beamprocess must be deleted before the beamprocessType. I illustrate this with a method below, but a short explanation is probably required.
A sequence holds cycles, which holds beamprocesses. These are 1-M private relationships so these objects are all deleted when the sequence is deleted. For some of the beamprocesses I also want to delete the associated beamprocessType. My problem is that when I call commit on the unit of work, TopLink tries to delete the beamprocessType before the associated beamprocess, which is not possible. How can I solve this?
Kind regards,
Katarina
The method:
public void deleteSequence(String name) throws PMException {
  SequenceController sequenceController = (SequenceController) ServiceLocator.getInstance().getService(SequenceController.class);
  Sequence sequence = sequenceController.getSequence(NameFactory.createSequenceName(name));
  PersistenceTransaction tx = PersistenceLayerFactory.getPersistenceLayer().acquireTransaction();
    // Delete all the "beam-out" beamprocess types and settings.
  Cycle[] cycles = sequence.getCycles();
  for (int i = 0; i < sequence.getCycles().length; i++) {
    BeamProcess[] bps = cycles.getBeamProcesses();
for (int j = 0; j < bps.length; j++) {
BeamProcess bp = bps[j];
if (bp.isBeamOut())
tx.deleteObject(bp.getType());
tx.deleteObject(sequence);
tx.commit();

Answer 1

Hi again,
I have now tried to modify my descriptor by adding the contstraint afterwards, but with no success:
      java.util.Map descriptors = project.getDescriptors();
      Descriptor descriptor = (Descriptor) descriptors.get(BeamProcessImpl.class);
      descriptor.addConstraintDependencies(BeamProcessTypeImpl.class);As mentioned in the previous posting, we do not use any mappings that are not specified in the mapping workbench, so TopLink should be able to order them properly. I include below the mapping descriptor for the BeamProcess class, with the hope that this will give you additional information to be able to help me solve this "mystery". I also include the error message.
Kind regards,
Katarina
Descriptor:
          <descriptor>
               <java-class>cern.macsy.core.domainimpl.BeamProcessImpl</java-class>
               <tables>
                    <table>CORE_BEAMPROCESS</table>
               </tables>
               <primary-key-fields>
                    <field>CORE_BEAMPROCESS.OID</field>
               </primary-key-fields>
               <descriptor-type-value>Normal</descriptor-type-value>
               <sequence-number-field>CORE_BEAMPROCESS.OID</sequence-number-field>
               <sequence-number-name>BP_SEQ</sequence-number-name>
               <identity-map-class>oracle.toplink.internal.identitymaps.SoftCacheWeakIdentityMap</identity-map-class>
               <remote-identity-map-class>oracle.toplink.internal.identitymaps.SoftCacheWeakIdentityMap</remote-identity-map-class>
               <identity-map-size>100</identity-map-size>
               <remote-identity-map-size>100</remote-identity-map-size>
               <should-always-refresh-cache>false</should-always-refresh-cache>
               <should-always-refresh-cache-on-remote>false</should-always-refresh-cache-on-remote>
               <should-only-refresh-cache-if-newer-version>false</should-only-refresh-cache-if-newer-version>
               <should-disable-cache-hits>false</should-disable-cache-hits>
               <should-disable-cache-hits-on-remote>false</should-disable-cache-hits-on-remote>
               <alias>BeamProcessImpl</alias>
               <copy-policy>
                    <descriptor-copy-policy>
                         <type>oracle.toplink.internal.descriptors.CopyPolicy</type>
                    </descriptor-copy-policy>
               </copy-policy>
               <instantiation-policy>
                    <descriptor-instantiation-policy>
                         <type>oracle.toplink.internal.descriptors.InstantiationPolicy</type>
                    </descriptor-instantiation-policy>
               </instantiation-policy>
               <query-manager>
                    <descriptor-query-manager>
                         <existence-check>Check cache</existence-check>
                    </descriptor-query-manager>
               </query-manager>
               <event-manager>
                    <descriptor-event-manager emptyAggregate="true">
                    </descriptor-event-manager>
               </event-manager>
               <mappings>
                    <-snipp->
                    <database-mapping>
                         <attribute-name>oid</attribute-name>
                         <read-only>false</read-only>
                         <field-name>CORE_BEAMPROCESS.OID</field-name>
                         <type>oracle.toplink.mappings.DirectToFieldMapping</type>
                    </database-mapping>
                    <-snipp->
                    <database-mapping>
                         <attribute-name>type</attribute-name>
                         <read-only>false</read-only>
                         <reference-class>cern.macsy.core.domainimpl.BeamProcessTypeImpl</reference-class>
                         <is-private-owned>false</is-private-owned>
                         <uses-batch-reading>false</uses-batch-reading>
                         <indirection-policy>
                              <mapping-indirection-policy>
                                   <type>oracle.toplink.internal.indirection.NoIndirectionPolicy</type>
                              </mapping-indirection-policy>
                         </indirection-policy>
                         <uses-joining>false</uses-joining>
                         <foreign-key-fields>
                              <field>CORE_BEAMPROCESS.BEAMPROCESS_TYPE</field>
                         </foreign-key-fields>
                         <source-to-target-key-field-associations>
                              <association>
                                   <association-key>CORE_BEAMPROCESS.BEAMPROCESS_TYPE</association-key>
                                   <association-value>CORE_BEAMPROCESSTYPE.OID</association-value>
                              </association>
                         </source-to-target-key-field-associations>
                         <type>oracle.toplink.mappings.OneToOneMapping</type>
                    </database-mapping>
               </mappings>
               <type>oracle.toplink.publicinterface.Descriptor</type>
          </descriptor>Error message:
[EXCEPTION [TOPLINK-4002] (TopLink - 9.0.3 (Build 423)): oracle.toplink.exceptions.DatabaseException
EXCEPTION DESCRIPTION: java.sql.SQLException: ORA-02292: integrity constraint (MACSYDEV.BEAMPROCESS_BPTYPE) violated - child record found
INTERNAL EXCEPTION: java.sql.SQLException: ORA-02292: integrity constraint (MACSYDEV.BEAMPROCESS_BPTYPE) violated - child record found
ERROR CODE: 2292]