Re: [TM4J-users] Casting TMAPI - TM4J Topic Problem

[Dicheva, D. <dic...@ws...>]

Hi Lars,

Thanks for your prompt reply.
=20
> [...]
> >   Collection vc =3D bn.getVariants();
> >   Iterator it =3D vc.iterator();
> >   while (it.hasNext()) {
> >      Variant var =3D (Variant) it.next();
> >      Iterator  si =3D var.getScope().iterator();     =20
> >      if (si.hasNext()){
> >         Topic param =3D (Topic)si.next(); //***Exception Here****
>=20
> > I get: JavaLangClassCastException:
> > Org.TM4J.TopicMap.Memory.TopicMapImpl
>=20

> Are you sure that your "Variant" is a "org.tmapi.core.Variant" and not
> a "org.tm4j.topicmap.Variant"? I've the suspicion that you mix up the
> classes from TM4J and TMAPI by mistake.

Well, the variant is TMAPI Variant - here is the value of "var" above:
org.tm4j.tmapi.core.TMAPIVariantImpl@75327fd8
The name is also an TMAPI name:=20

I divided Iterator  si =3D var.getScope().iterator();   into

	Set s =3D var.getScope();
	Iterator  si =3D s.iterator();

So, now the picture is:
     Collection vc =3D bn.getVariants();
     Iterator it =3D vc.iterator();
     while (it.hasNext()) {
        Variant var =3D (Variant) it.next();
        Set s =3D var.getScope();
	  Iterator  si =3D s.iterator();     =20
        if (si.hasNext()){
           Topic param =3D (Topic)si.next(); //***Exception Here****
 =20

and just before the exception I have:

var: org.tm4j.tmapi.core.TMAPIVariantImpl@75327fd8
but in the Set s:  HashMap -> Table -> HashMap$Entry -> key [4] =3D
org.tm4j.topicmap.memory.TopicImpl@d00f8c41

and the imports are:

import java.util.Collection;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Set;

import org.tmapi.core.Locator;
import org.tmapi.core.Topic;
import org.tmapi.core.TopicMap;
import org.tmapi.core.TopicName;
import org.tmapi.core.Variant;
import org.tmapi.index.core.TopicNamesIndex;

So, I am not using TM4J directly, only TMAPI. Which means that the TMAPI
getScope() applied on the TMAPI variant var returns an unmodifiable set
of TM4J topics and that is why I am getting the cast exception.

> If you need to work with TM4J interfaces *and* TMAPI interfaces, the
> class "org.tm4j.tmapi.helpers.Wrapper" may help you to 'wrap' and
> 'unwrap' objects into both directions.

I don't really want to work with both interfaces, so I only use the
TMAPI interface.

Any further idea?=20

Thanks,
Darina


>=20
> Best regards,
> Lars
> --=20
> http://www.semagia.com
> http://www.topicgarden.com/mailinglist/ German Topic Maps mailinglist
>=20
>=20