The notion of "apply to a class" in OWL is not like it is in object
oriented languages.
For discussion on this see:
http://jena.apache.org/documentation/notes/rdf-frames.html
In particular see the listDeclaredProperties helper function which is
mentioned therein.
Dave
On 19/03/13 15:07, Ed Swing wrote:
On to my next unexplainable thing in Jena – Property domains. The code
below is trying to identify what properties apply to a class based on
the property domain. Here’s the code:
*package*ontology;
*import*java.io.FileInputStream;
*import*java.io.IOException;
*import*java.util.Iterator;
*import*com.hp.hpl.jena.ontology.*;
*import*com.hp.hpl.jena.rdf.model.ModelFactory;
/**
* *@author*<a _href_="http://www.ganae.com/edswing";>Edward Swing</a>
*/
*public**class*PropTest {
/**
* *TODO*: DOCUMENT ME
*
* *@param*args
* *@throws*IOException
*/
*public**static**void*main(String[] args) *throws*IOException {
OntModel model =
ModelFactory./createOntologyModel/(OntModelSpec./OWL_DL_MEM_RULE_INF/);
FileInputStream inStream =
*new*FileInputStream("ontology/terrorism.xml");
model.read(inStream, *null*);
inStream.close();
String uriBase = model.getNsPrefixURI("");
OntClass cls = model.getOntClass(uriBase + "TerrorAttack");
System./out/.println(cls);
*for*(Iterator<OntProperty> iter = model.listAllOntProperties(); iter
.hasNext();) {
OntProperty prop = iter.next();
OntResource res = prop.getDomain();
*if*(res != *null*&& res.isURIResource() && res.isClass()) {
*try*{
OntClass dom = res.asClass();
*if*(cls.hasSuperClass(dom)) {
System./out/.println("Prop: "+ prop + " (domain: "
+ dom + ")");
}
} *catch*(ConversionException exc) {
}
}
}
}
}
Here’s what is printed:
http://blsdev1.vsticorp.com/terrorism#TerrorAttack
Prop: http://blsdev1.vsticorp.com/terrorism#numberKilled (domain:
http://blsdev1.vsticorp.com/terrorism#Killing)
Prop: http://blsdev1.vsticorp.com/terrorism#isSuicide (domain:
http://blsdev1.vsticorp.com/terrorism#TerrorAttack)
Prop: http://blsdev1.vsticorp.com/terrorism#eventType (domain:
http://blsdev1.vsticorp.com/terrorism#Event)
Prop: http://blsdev1.vsticorp.com/terrorism#numberInjured (domain:
http://blsdev1.vsticorp.com/terrorism#Killing)
Prop: http://blsdev1.vsticorp.com/terrorism#weaponType (domain:
http://blsdev1.vsticorp.com/terrorism#Killing)
Prop: http://blsdev1.vsticorp.com/terrorism#destination (domain:
http://www.w3.org/2002/07/owl#Thing)
Prop: http://blsdev1.vsticorp.com/terrorism#relatedEvent (domain:
http://www.w3.org/2002/07/owl#Thing)
Prop: http://blsdev1.vsticorp.com/terrorism#victim (domain:
http://www.w3.org/2002/07/owl#Thing)
Prop: http://blsdev1.vsticorp.com/terrorism#inCountry (domain:
http://www.w3.org/2002/07/owl#Thing)
Prop: http://blsdev1.vsticorp.com/terrorism#forCountry (domain:
http://www.w3.org/2002/07/owl#Thing)
Prop: http://blsdev1.vsticorp.com/terrorism#regionOfInfluence (domain:
http://www.w3.org/2002/07/owl#Thing)
Prop: http://blsdev1.vsticorp.com/terrorism#actor (domain:
http://www.w3.org/2002/07/owl#Thing)
Prop: http://blsdev1.vsticorp.com/terrorism#organizationsInBody
(domain: http://www.w3.org/2002/07/owl#Thing)
Prop: http://blsdev1.vsticorp.com/terrorism#eventDate (domain:
http://www.w3.org/2002/07/owl#Thing)
Prop: http://blsdev1.vsticorp.com/terrorism#isNearTo (domain:
http://www.w3.org/2002/07/owl#Thing)
Prop: http://blsdev1.vsticorp.com/terrorism#personsInBody (domain:
http://www.w3.org/2002/07/owl#Thing)
Prop: http://blsdev1.vsticorp.com/terrorism#responsibleFor (domain:
http://www.w3.org/2002/07/owl#Thing)
Prop: http://blsdev1.vsticorp.com/terrorism#hasLocation (domain:
http://www.w3.org/2002/07/owl#Thing)
Prop: http://blsdev1.vsticorp.com/terrorism#locatedIn (domain:
http://www.w3.org/2002/07/owl#Thing)
Prop: http://blsdev1.vsticorp.com/terrorism#reportedBy (domain:
http://www.w3.org/2002/07/owl#Thing)
Prop: http://blsdev1.vsticorp.com/terrorism#hasTopic (domain:
http://www.w3.org/2002/07/owl#Thing)
Prop: http://blsdev1.vsticorp.com/terrorism#isPartOf (domain:
http://www.w3.org/2002/07/owl#Thing)
Prop: http://blsdev1.vsticorp.com/terrorism#locationsInBody (domain:
http://www.w3.org/2002/07/owl#Thing)
Prop: http://blsdev1.vsticorp.com/terrorism#hasMember (domain:
http://www.w3.org/2002/07/owl#Thing)
Several of these are incorrect. For instance, organizationsInBody
explicitly has a domain of NewsArticle:
<owl:ObjectProperty rdf:ID="organizationsInBody">
<rdfs:domain rdf:resource="#NewsArticle" />
<rdfs:range rdf:resource="#Organization" />
</owl:ObjectProperty>
The Javadoc description for getDomain() is “Answer a resource that
represents the domain class of this property. If there is more than one
such resource, an arbitrary selection is made.”
If the domain of a property can be generalized into Thing (trivially
true) then this method is useless – all it has to do is return Thing
every time to be technically correct.
*Edward Swing*
*Applied Research Technologist*
*Vision Systems + Technology, Inc., a SAS Company*
6021 University Boulevard • Suite 360 • Ellicott City • Maryland • 21043
*Tel:*410.418.5555 *Ext:*919 • *Fax:*410.418.8580
*Email*:[email protected] <mailto:[email protected]>
*Web:*http://www.vsticorp.com <http://www.vsticorp.com/>
