RDF Parsing resolving empty URI

Hi -

a user (Sean Bechhofer) discovered a possible bug within our parser.
However we are not sure, whether it is a bug. What is the correct
behaviour when having an empty rdf:ID ? Take for example:

<owl:Ontology rdf:ID="" />

We found the RDF specification to be quite ambiguous with respect to this
issue. Namely, they say I should
resolve any URI against the XML base. Well, this is exactly what we do. We
are
using Java's methods for this. However, Java resolves against the file name
if no
XML base is specfied but chops off things from the URI:

For example, the URI http://xyz.com/ontologies/animals is interpreted as a
file URI (as doesn't end with a slash).
Then Java thinks it should chop off  the last file name and replace it with
your relative URI, which is empty. Hence,
http://xyz.com/ontologies/ is the correct resolution of an empty  URI
against
the URI http://xyz.com/ontologies/animals.


The only thing how one could really get http://xyz.com/ontologies/animals
back is if we would test for the empty ID. We can do that, but we
really don't know what is correct. We tried to look this up in the spec, but
we
didn't find anything that would answer our question. Hence we left it as it
is.

If you have any evidence we should really test the empty case, please let us
know and we do this immediately - this is a one-liner.

Best,

Boris Motik & Raphael Volz

Received on Monday, 13 October 2003 12:24:37 UTC