Query query = QueryFactory.create(Req) ;
QueryExecution qexec = QueryExecutionFactory.create(query, model) ;
ResultSet results = qexec.execSelect();
List<String> profs = new ArrayList<String>();
while(results.hasNext()){
QuerySolution rs = results.nextSolution();
Resource prof = rs.getResource("prof");
profs.add(prof.getLocalName());
}
int random = (int)(Math.random() * profs.size()-1);
resultatRDF[1][0] = "professeur"; resultatRDF[1][1] = profs.get(random);