> You claim it's illegal. Why? Did I? I pointed out the scenario, and asked if Jena's API can help handle it. Are you claiming the "congress people" RDF/XML graph is illegal?
Doesn't really matter, what matters is this scenario will play out in many RDF/XML graphs. We want to use JENA, but we have to be able to support RDF/XML graphs such as the congress people... >The Turtle way is much better for RDF - we have to live with RDF/XML for >awhile though. >You can call the Turtle writer directly with a PrefixMap , whic is more >liberal than the PrefixMapping the XML writer needs. At this point, I'll try anything. Read in the people graph, wrote out as turtle, read in turtle version, still having issues same issues with numeric people ids and all .jpg resources. Anything else that I could do? Thanks, Rodrigo. -----Original Message----- From: Andy Seaborne [mailto:[email protected]] Sent: Wednesday, March 27, 2013 2:52 PM To: [email protected] Subject: Re: RDF Model Namespaces On 27/03/13 18:29, Pastrana, Rodrigo (RIS-BCT) wrote: >> Because "410069.jpeg" is illegal as an XML qname local part, it is not >> returned by Jena. > > So basically, a Jena API user interested in a node's NS and name will > need to extract the full URI and parse it manually to extract the NS > and the Name. Because the > com.hp.hpl.jena.rdf.model.Resource.getNameSpace() will potentially > return invalid namespaces (if the name starts with a numeral or > contains a dot). You claim it's illegal. Why? Let's look at XML namespace 1.0 edition 3: A names pace is used in a qname which is the PrefixedName gramam production: [8] PrefixedName ::= Prefix ':' LocalPart [10] Prefix ::= NCName /* An XML Name, minus the ":" */ [4] NCName ::= Name - (Char* ':' Char*) [5] Name ::= NameStartChar (NameChar)* Name and NameStarChar exclude "/" so the local part can't include "/" so ("http://www.rdfabout.com/rdf/usgov/congress/";, "people/412360") does not work either. > Being able to navigate every statement in an RDF graph is one of the reasons > we are considering JENA, where can we add a feature request for this API? > Thanks. > > Another example is Woodrow Wilson's congress people entry. > <foaf:Person > rdf:about="http://www.rdfabout.com/rdf/usgov/congress/people/412360";> > ... > </foaf:Person> > > Jena represents the statement like this: > [http://www.rdfabout.com/rdf/usgov/congress/people/412360, > http://www.w3.org/1999/02/22-rdf-syntax-ns#type, > http://xmlns.com/foaf/0.1/Person] > > But the Subjec'ts namespaces is reported as > "http://www.rdfabout.com/rdf/usgov/congress/people/412360"; and it's localname > as "". Which is correct. A local part can't start with a digit. [11] LocalPart ::= NCName XML allows an empty local part. In Turtle, you can define the prefix (which is not an XML namspace) as "http://www.rdfabout.com/rdf/usgov/congress/people/"; and get ns:412360 but it's not legal as an XML qname. The Turtle way is much better for RDF - we have to live with RDF/XML for awhile though. You can call the Turtle writer directly with a PrefixMap , whic is more liberal than the PrefixMapping the XML writer needs. Andy > > > Thanks, Rodrigo. > > -----Original Message----- > From: Andy Seaborne [mailto:[email protected]] > Sent: Tuesday, March 26, 2013 8:56 AM > To: [email protected] > Subject: Re: RDF Model Namespaces > > On 25/03/13 17:19, Pastrana, Rodrigo (RIS-BCT) wrote: >> In order to use Jena's API to navigate RDF graphs, I need to know how >> this particular node is represented. If the node were a literal, its >> literallexicalform would be sufficient. Since the node is represented >> as an instance of "Resource" the node's label is the namespace + the >> localname. However, "http://www.govtrack.us/data/photos/410069."; Is >> clearly not a NS, and "jpeg" is not its local name. >> >> Using Jena's API how can one determine if the given "Resource" node >> can represented by its literallexicalform, or by its >> namespace+localname. Thanks. > > The full URI should be what you use to determine if two Resources are the > same. Namespace/localpart are just syntactic convenience - the code keeps > and indexes URIs only. > > For literals, you need to test the language or datatype as well. > > "123" is not the integer 123. > > You can use .equals (of RDFNode, the supertype of Resource and > Literal) > > A Resource is a URI or a blank node. > > RDFNode has isLiteral()/isURIResource()/isResource()/isAnon() for testing > what kind of thing an RDFNode is. > > By XML, ("http://www.govtrack.us/data/photos/410069.","jpeg";) is a > qname > - in fact the one with the longest local part. > > This is a qname ("http://www.govtrack.us/data/photos/410069.jp";, "eg") for > the same URI. > > Because "410069.jpeg" is illegal as an XML qname local part, it is not > returned by Jena. > > Roll on Turtle ... > > Andy > > ----------------------------------------- > The information contained in this e-mail message is intended only for > the personal and confidential use of the recipient(s) named above. > This message may be an attorney-client communication and/or work > product and as such is privileged and confidential. 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