Hi Marian, The problem can be detected from the output: Your class sk.euromove.goldeneye.projectmanagement.bos.Project has an attribute allSubsystems of type java.util.Vector
If you are using prox="true" OJB builds a CollectionProxy instance and tries to set the attribute allSubsystems to this value. But a CollectionProxy can't be downcasted to java.util.Vector! Please try to declare allSubsystems as java.util.Collection or java.util.List. cheers, Thomas > -----Ursprüngliche Nachricht----- > Von: Marian Skalsky [mailto:[EMAIL PROTECTED]] > Gesendet: Dienstag, 5. November 2002 15:35 > An: OJB Users List > Betreff: collection-descriptor + collection proxy > > > Hi there! > Can somebody please explain some things I'm not completely sure of ? > I'm having problem when set proxy="true" with 1:n collection > descriptor. I > got "argument mismatch exception".. and I have no idea why. > Here is the > output: > [DEFAULT] ERROR: Error in operation [set] of object > [PersistentFieldPropertyImpl], java.lang.IllegalArgumentException > [DEFAULT] ERROR: Declaring class > [sk.euromove.goldeneye.projectmanagement.bos.Project] > [DEFAULT] ERROR: Property Name [allSubsystems] > [DEFAULT] ERROR: Property Type [java.util.Vector] > [DEFAULT] ERROR: anObject was class > [sk.euromove.goldeneye.projectmanagement.bos.Project] > [DEFAULT] ERROR: aValue was class > [org.apache.ojb.broker.accesslayer.CollectionProxy] > java.lang.IllegalArgumentException: argument type mismatch > rethrown as org.apache.ojb.broker.PersistenceBrokerException: > argument type > mismatch > Caused by: java.lang.IllegalArgumentException: argument type mismatch > > Everithing works fine, till I put proxy="true". > 1) Don't you know what may cause this ? answered above > 2) proxy="true" means that when OBJECT is loaded using e.g. > getObjectByQuery, asociated elements are not > loaded/materialized imidiately, > but only at request or call of .size() ? correct. > 3) The class participating in this relationship do not need > to implement > anything to be used in a collection proxy ? Must implement Collection, List or ManageableCollection. cheers, Thomas > > Thank you a lot. > $kala. > > > -- > To unsubscribe, e-mail: > <mailto:[EMAIL PROTECTED]> > For additional commands, e-mail: > <mailto:[EMAIL PROTECTED]> > > -- To unsubscribe, e-mail: <mailto:[EMAIL PROTECTED]> For additional commands, e-mail: <mailto:[EMAIL PROTECTED]>
