Re: AW: [OJB-developers] Using CollectionDescriptor in repository.xml

[Leandro R. S. C. <le...@ib...>]

Sorry man, in fact the problem was in another line at repository.xml
I defined a ReferenceDescriptor that pointed to the wrong class field.


By the way. If I have a association like this A 1 ----- N B

Do I have to defined CollectionDescriptors(from A to B) and
ReferenceDescriptos( from B to A) or just one of them ??


On Fri, 2002-03-22 at 12:20, Mahler Thomas wrote:
> Hi Leandro,
>=20
> I'll try to explain the 1-n section from the tutorial3.
> Say you have a class ProductGroup with a Vector attribute allArticlesInGr=
oup
>  that holds all Article objects belonging to this group.
>=20
> That is: *one* ProductGroup holds *n* Articles.
>=20
> You must tell OJB how to load the allArticlesInGroup attribute on loading=
 a
> ProductGroup object.
> This is done by the following CollectionDescriptor:
> <ClassDescriptor id=3D"2">
>       <class.name>test.ojb.broker.ProductGroup</class.name>
> 	...
>       <CollectionDescriptor id=3D"1">
>          <cdfield.name>allArticlesInGroup</cdfield.name>
>          <items.class>test.ojb.broker.Article</items.class>
>          <inverse_fk_descriptor_ids>4</inverse_fk_descriptor_ids>
>       </CollectionDescriptor>
> 	...
>=20
> This descriptor contains the following info:
> - The class ProductGroup has a container attribute allArticlesInGroup.=20
>   The Java-type of this attribute is not declared. It maybe of type
> SomeType[],=20
>   Collection, or ManageableCollection.
> - The Items in this Container are of type Article
> - The Mapping of class Article has a attribute with id=3D"4" that holds a=
=20
>   foreign key value idetifying the associated ProductGroup
>=20
> HTH,
>=20
> Thomas
>=20
> > -----Urspr=FCngliche Nachricht-----
> > Von: Leandro Rodrigo Saad Cruz [mailto:le...@ib...]
> > Gesendet: Freitag, 22. M=E4rz 2002 15:30
> > An: obj...@li...
> > Betreff: [OJB-developers] Using CollectionDescriptor in repository.xml
> >=20
> >=20
> > Hi all. There is one thing I didn't understand from the docs about
> > association mapping
> > http://objectbridge.sourceforge.net/tutorial3.html#1-n
> >=20
> > <CollectionDescriptor id=3D"1">
> >    <cdfield.name>collection</cdfield.name>=20
> >    ******* -> does this field must be present in repository.xml in
> > SomeCLASS ClassDescriptor ? or just be a field in SomeCLASS impl ?
> >=20
> >    <items.class>SomeCLASS</items.class>
> >    <inverse_fk_descriptor_ids>2</inverse_fk_descriptor_ids>
> > </CollectionDescriptor>
> >=20
> > I keep getting exceptions like this :
> > Expcetion : java.util.NoSuchElementException
> > StackTrace: java.util.NoSuchElementException at
> > ojb.broker.accesslayer.RsIterator.next(RsIterator.java) at
> > ojb.broker.singlevm.PersistenceBrokerImpl.getCollectionByQuery
> > (PersistenceBrokerImpl.java:931)at=20
> > ojb.broker.singlevm.PersistenceBrokerImpl.getCollectionByQuery
> > (PersistenceBrokerImpl.java:1000)at=20
> > ojb.broker.singlevm.PersistenceBrokerImpl.getCollectionByQuery
> > (PersistenceBrokerImpl.java:1093)at=20
> > ojb.broker.singlevm.PersistenceBrokerImpl.getCollectionByQuery
> > (PersistenceBrokerImpl.java:1080)at
> > ....
> >=20
> > that doesn't help me so much.
> >=20
> >=20
> > --=20
> > Leandro Rodrigo Saad Cruz
> > IT - Inter Business Tecnologia e Servicos (IB)
> > http://www.ibnetwork.com.br
> >=20
> >=20
> > _______________________________________________
> > Objectbridge-developers mailing list
> > Obj...@li...
> > https://lists.sourceforge.net/lists/listinfo/objectbridge-developers
> >=20
--=20
Leandro Rodrigo Saad Cruz
IT - Inter Business Tecnologia e Servicos (IB)
http://www.ibnetwork.com.br