Thanks a lot Dave, let me try it. I hope it will help. Regards
On Sun, Sep 18, 2016 at 1:28 PM, Dave Reynolds <dave.e.reyno...@gmail.com> wrote: > On 18/09/16 21:24, javed khan wrote: > >> Thanks Lorenz and Dave, I have corrected the http://www.semanticweb.org# >> <http://www.semanticweb.org/#GPA>Student to ?x but it does not >> work.Actually it does not save the updated marks/GPA of student and when I >> remove the Jena rules part, it then updates and save the GPA. >> I also try the SPARQL query inside Protege Query tab but it does not give >> me any instance of the GoodStudent class. >> > > The example I showed does work. If you write inf to file or std out you > can see the class, if you run your sparql query it lists s1. > > Dave > > > On Sun, Sep 18, 2016 at 12:40 PM, Lorenz Buehmann < >> buehm...@informatik.uni-leipzig.de> wrote: >> >> The second condition of your rule doesn't make any sense as the subject >>> is Student and it should be ?x. >>> >>> >>> On 18.09.2016 17:41, javed khan wrote: >>> >>>> This code does not work. I want to save student marks/GPA in the file >>>> and >>>> based on GPA assign students to GoodStudent or WorstStudents sub classes >>>> >>> of >>> >>>> Student via Jena rules. >>>> >>>> >>>> >>>> >>>> OntModel model=ModelFactory.createOntologyModel(); >>>> >>>> InputStream in =FileManager.get().open("C://std.owl"); >>>> if (in==null) { >>>> throw new IllegalArgumentException( "File: " + " not >>>> found"); >>>> } model.read(in,""); >>>> >>>> String ns="http://www.semanticweb.org#";; >>>> >>>> OntClass user1 = model.getOntClass(ns + "Student"); >>>> >>>> Individual indiv = user1.createIndividual(ns + name); //name >>>> >>> is >>> >>>> variable >>>> >>>> Property prop= model.getProperty(ns,"GPA"); >>>> >>>> indiv.addLiteral(prop, marks); //marks also variable having >>>> some value i-e 3.0 >>>> >>>> >>>> >>>> String rule="[rule1:(?x http://www.w3.org/1999/02/22- >>>> >>> rdf-syntax-ns#type >>> >>>> http://www.semanticweb.org#Student) " + >>>> "( http://www.semanticweb.org#Student >>>> http://www.semanticweb.org#GPA ?marks + )" + "greaterThan(?marks, >>>> >>> 2) "+ >>> >>>> " -> (?x http://www.w3.org/1999/02/22-rdf-syntax-ns#type >>>> http://www.semanticweb.org#GoodStudent )]"; >>>> >>>> String queryString= "PREFIX std:<http://www.semanticweb. >>>> >>> org#> >>> >>>> "+ >>>> "PREFIX rdfs:<http://www.w3.org/2000/01/rdf-schema#> " + >>>> "PREFIX rdf:<http://www.w3.org/1999/02/22-rdf-syntax-ns#> "+ >>>> "SELECT * " + >>>> " WHERE { ?x rdf:type std:GoodStudent}"; >>>> >>>> Reasoner reasoner2 = new >>>> GenericRuleReasoner(Rule.parseRules(rule)); >>>> InfModel inf = ModelFactory.createInfModel(reasoner2, model); >>>> Query query = QueryFactory.create(queryString); >>>> QueryExecution qe = QueryExecutionFactory.create(query, inf); >>>> ResultSet results = qe.execSelect(); >>>> ResultSetFormatter.out(System.out, results, query); >>>> qe.close(); >>>> >>>> >>>> >>>> try (FileOutputStream writer = new >>>> FileOutputStream("C://std.owl")) { >>>> model.write(writer, "RDF/XML"); >>>> } catch (IOException ex) { >>>> Logger.getLogger(stdinfo.class.getName()).log(Level.SEVERE, >>>> null, ex); >>>> } >>>> model.write(System.out, "N3"); >>>> >>>> } >>>> >>>> >>> >>> >> >
