DBpedia Jena Query returning null
dbpedia, java, jena, rdf, sparql
Solution
that is so embarassing, there is space problem in the query:
String service = "http://dbpedia.org/sparql";
String queryString = "";
queryString = "PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#> SELECT ?label " +
"WHERE {" +
"<http://dbpedia.org/resource/Quatre_Bornes> <http://dbpedia.org/ontology/country> ?y ."+
"?y rdfs:label ?label ."+
"FILTER (LANG(?label) = 'en')"+
"}";
Problem
I'm just trying to run a small query on DBpedia, the query itself works, see it here, but I don't why its returning when doing so with Jena, I'm getting null. ``` String service = "http://dbpedia.org/sparql"; String queryString = ""; queryString = "PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#> SELECT ?label" + "WHERE {" + "<http://dbpedia.org/resource/Quatre_Bornes> <http://dbpedia.org/ontology/country> ?y ."+ "?y rdfs:label ?label ."+ "FILTER (LANG(?label) = 'en')"+ "}"; Query query = QueryFactory.create(queryString); QueryEngineHTTP qexec = QueryExecutionFactory.createServiceRequest(service, query); ResultSet results = qexec.execSelect(); for ( ; results.hasNext() ; ) { QuerySolution soln = results.nextSolution() ; System.out.println(soln.getLiteral("label")); } ``` Any suggestion?