[mdr-users] Re: XML Namespaces and Custom Metamodels

Looking at the XMI and the Java code over and over again, I can't find
why the Node element cannot be found.  Removing the "tracing." prefix
didn't solve the problem.  I wonder how it's possible that MDR was
able to write XMI that it cannot read again without throwing
exceptions...

Any ideas?

Kind regards,
-- Pieter.

On 8/4/05, Pieter Van Gorp <[email protected]> wrote:
> I may have been too fast by assuming that the exception was caused by
> an XML namespace problem.  In fact, I now believe that the XMI reader
> (XML parser) is looking for elements in the default (nameless)
> namespace and cannot find elements like "tracing.Node".  I'm not sure
> why the parser complains about an unknown "package" instead of an
> unknown "element" though...
> 
> Keep in touch,
> Pieter.
> 
> On 8/4/05, Pieter Van Gorp <[email protected]> wrote:
> > Hi all,
> > how can I set the XML namespace to be used in the XMI for models
> > conforming to my own metamodel?
> >
> > I've created a metamodel for creating traceability links across UML
> > models.  Therefore, my metamodel clusters the UML metamodel (more info
> > on http://www.fots.ua.ac.be/motmot/docs/traceability-p3.php).  The
> > problem is that when I serialize a traceability model to XMI, only
> > "UML" is defined as an XML namespace and "tracing" (which should be
> > the namespace for elements in the clustering model) is undefined.
> >
> > This leads to exceptions when the XMI is read in again.  For example:
> > org.netbeans.lib.jmi.util.DebugException: Element name cannot be
> > resolved, unknown package: tracing.Node
> >         at org.netbeans.lib.jmi.xmi.XmiContext.resolveElementName(XmiContext.java:527)
> >         at org.netbeans.lib.jmi.xmi.XmiElement$Content.startSubElement(XmiElement.java:354)
> >         at org.netbeans.lib.jmi.xmi.XmiSAXReader.startElement(XmiSAXReader.java:223)
> >
> > XMI of the erraneous traceability model:
> > <?xml version = '1.0' encoding = 'ISO-8859-1' ?>
> > <XMI xmi.version = '1.2' xmlns:UML = 'org.omg.xmi.namespace.UML'
> > timestamp = 'Thu Aug 04 15:51:23 CEST 2005'>
> >   <XMI.header>
> >     <XMI.documentation>
> >       <XMI.exporter>Netbeans XMI Writer</XMI.exporter>
> >       <XMI.exporterVersion>1.0</XMI.exporterVersion>
> >     </XMI.documentation>
> >   </XMI.header>
> >   <XMI.content>
> >     <tracing.Node xmi.id = 'a1' role = 'reference to a1'>
> >       <tracing.Node.trace>
> >         <tracing.Trace xmi.idref = 'a2'/>
> >       </tracing.Node.trace>
> >       <tracing.Node.content>
> >         <UML:Attribute xmi.idref = 'a3'/>
> >       </tracing.Node.content>
> >     </tracing.Node>
> >     <tracing.Node xmi.id = 'a4' role = 'reference to a2'>
> >       <tracing.Node.trace>
> >         <tracing.Trace xmi.idref = 'a2'/>
> >       </tracing.Node.trace>
> >       <tracing.Node.content>
> >         <UML:Attribute xmi.idref = 'a5'/>
> >       </tracing.Node.content>
> >     </tracing.Node>
> >     <tracing.Trace xmi.id = 'a2'>
> >       <tracing.Trace.node>
> >         <tracing.Node xmi.idref = 'a1'/>
> >         <tracing.Node xmi.idref = 'a4'/>
> >       </tracing.Trace.node>
> >     </tracing.Trace>
> >   </XMI.content>
> > </XMI>
> > I thought it may be due to a missing tag in the specification of my
> > metamodel but couldn't find a solution on the website for the UML
> > profile for MOF...
> >
> > Thanks in advance for your help,
> > --
> > Pieter Van Gorp
> >        Teaching and Research Assistant
> >        FOrmal Techniques in Software engineering (FOTS)
> >        University of Antwerp
> >        Middelheimlaan 1
> >        2020 Antwerpen - Belgium
> >        Office: G.304
> >        Phone: +32 3 265 38 71
> >        Fax: +32 3 265 37 77
> >        http://www.fots.ua.ac.be/~pvgorp/research/
> >        http://motmot.sourceforge.net/
> >
>