Re: Status of the Dublin Core to Topic Maps mapping?

Hi Lars

Unfortunately there is no written documentation about the Dublin Core to 
Topic maps conversion features of Wandora. At the moment best 
documention is Wandora's source code. DC RDF extractor's source classes are

org.wandora.application.tools.extractors.rdf.DublinCoreRDFExtractor
org.wandora.application.tools.extractors.rdf.rdfmappings.DublinCoreMapping

and DC XML extractor's source class is

org.wandora.application.tools.extractors.dublincore.DublinCoreXMLExtractor



In RDF mapping the value of "dc:creator" and "dc:publisher" is mapped to 
a topic if the value is a resource. RDF resource is used as a subject 
identifier of the value topic. If the value is a literal then an 
occurrence is created for it. Thus, depending on the original DC RDF, 
the value of "dc:creator" and "dc:publisher" may be a topic or an 
occurrence.


XML mapping is different. In XML mapping, the value of "dc:creator" and 
"dc:publisher" is always mapped to a topic. Wandora gives a subject 
identifier for the value topic of "dc:creator" using a pattern:

http://purl.org/dc/elements/1.1/creator/<value-of-the-creator>

where the last part is the value as a string. Similarly, Wandora gives 
the publisher topic a subject identifier

http://purl.org/dc/elements/1.1/publisher/<value-of-the-publisher>

Both creator and publisher topics are named with the value string using 
unconstraint scope. If names are equal, topics merge.

And before anyone throws a stone, yes, I know that subject identifiers 
used in DC XML mapping are very poor. But somehow, that is everything we 
really know about the subject of, say creator, at the time mapping is 
realized. Sure one can polish and change these autogenerated subjects 
later on when better identifiers become available.

Kind Regards,
Aki / Wandora Team




On 7.10.2010 12:32, Lars Heuer wrote:
> Hi Aki,
>
> [...]
>> I invite you to try Wandora's conversion implementations. Wandora
>> has two different DC to TM mappings:
> [...]
>
> Is the translation documented somewhere?
>
> How do you handle dc:creator / dc:publisher? Do you create a topic for
> them? Do you treat them as occurrences? And if you create topics, how
> do you assign an identity to them?
>
> Best regards,
> Lars