Ejemplo n.º 1
0
 /**
  * Example the conclusions graph for introduction of restrictions which require a comprehension
  * rewrite and declare new (anon) classes for those restrictions.
  */
 public void comprehensionAxioms(Model premises, Model conclusions) {
   // Comprehend all restriction declarations and note them in a map
   Map<Resource, Resource> comprehension = new HashMap<>();
   StmtIterator ri = conclusions.listStatements(null, RDF.type, OWL.Restriction);
   while (ri.hasNext()) {
     Resource restriction = ri.nextStatement().getSubject();
     StmtIterator pi = restriction.listProperties(OWL.onProperty);
     while (pi.hasNext()) {
       Resource prop = (Resource) pi.nextStatement().getObject();
       StmtIterator vi = restriction.listProperties();
       while (vi.hasNext()) {
         Statement rs = vi.nextStatement();
         if (!rs.getPredicate().equals(OWL.onProperty)) {
           // Have a restriction on(prop) of type rs in the conclusions
           // So assert a premise that such a restriction could exisit
           Resource comp =
               premises
                   .createResource()
                   .addProperty(RDF.type, OWL.Restriction)
                   .addProperty(OWL.onProperty, prop)
                   .addProperty(rs.getPredicate(), rs.getObject());
           comprehension.put(restriction, comp);
         }
       }
     }
   }
   // Comprehend any intersectionOf lists. Introduce anon class which has the form
   // of the intersection expression.
   // Rewrite queries of the form (X intersectionOf Y) to the form
   //   (X equivalentClass ?CC) (?CC intersectionOf Y)
   StmtIterator ii = conclusions.listStatements(null, OWL.intersectionOf, (RDFNode) null);
   List<Statement> intersections = new ArrayList<>();
   while (ii.hasNext()) {
     intersections.add(ii.nextStatement());
   }
   for (Statement is : intersections) {
     // Declare in the premises that such an intersection exists
     Resource comp =
         premises
             .createResource()
             .addProperty(RDF.type, OWL.Class)
             .addProperty(
                 OWL.intersectionOf, mapList(premises, (Resource) is.getObject(), comprehension));
     // Rewrite the conclusions to be a test for equivalence between the class being
     // queried and the comprehended interesection
     conclusions.remove(is);
     conclusions.add(is.getSubject(), OWL.equivalentClass, comp);
   }
   // Comprehend any oneOf lists
   StmtIterator io = conclusions.listStatements(null, OWL.oneOf, (RDFNode) null);
   while (io.hasNext()) {
     Statement s = io.nextStatement();
     Resource comp = premises.createResource().addProperty(OWL.oneOf, s.getObject());
   }
 }
Ejemplo n.º 2
0
 /**
  * Helper. Adds to the target model a translation of the given RDF list with each element replaced
  * according to the map.
  */
 private Resource mapList(Model target, Resource list, Map<Resource, Resource> map) {
   if (list.equals(RDF.nil)) {
     return RDF.nil;
   } else {
     Resource head = (Resource) list.getRequiredProperty(RDF.first).getObject();
     Resource rest = (Resource) list.getRequiredProperty(RDF.rest).getObject();
     Resource mapElt = target.createResource();
     Resource mapHead = map.get(head);
     if (mapHead == null) mapHead = head;
     mapElt.addProperty(RDF.first, mapHead);
     mapElt.addProperty(RDF.rest, mapList(target, rest, map));
     return mapElt;
   }
 }