jena

I'm trying to build a small semantic web application using Jena framework, JSP and JAVA. I have a remote SPARQL endpoint and I've already written a simple query which works fine but now I need to use some parameters. Here is my code so far: final static String serviceEndpoint = "http://fishdelish.cs.man.ac.uk/sparql/"; String comNameQuery = "PREFIX fd: <http://fishdelish.cs.man.ac.uk/rdf/vocab/resource/> " + "SELECT ?name ?language ?type" + "WHERE { ?nameID fd:comnames_ComName ?name ;" + "fd:comnames_Language ?language ;" + "fd:comnames_NameType ?type ." + "}"; Query query = QueryFactory

Same query works in DBpedia Endpoint( http://ko.dbpedia.org/sparql ), but not in my Java code. I am just trying to extract the frequency using "COUNT" function. VirtGraph set = new VirtGraph("http://ko.dbpedia.org", HOST, USERNAME, PASSWORD); Query freqsparql = QueryFactory.create("SELECT ?class count(distinct ?s) as ?count where{?s <http://ko.dbpedia.org/property/이름> ?o. ?s a ?class.} order by DESC(?count)"); VirtuosoQueryExecution freqvqe = VirtuosoQueryExecutionFactory.create(freqsparql, set); ResultSet freqresults = freqvqe.execSelect(); And the error is as follows. Exception in thread

I'm using Jena to write a rdf file that describes online posts. According to the sioc ontology/namespace that I'm using there is, for instance, the following: Class: sioc:Post Property: sioc:has_creator How can I, in Jena, include the sioc:Post in the file as <sioc:Post rdf:about="http://example.com/vb/1035092"> instead of <rdf:Description rdf:about="http://example.com/vb/1035092"> and what is the best practice? Joshua Taylor Both of the answers so far make good points: You should not pay much attention to the particular serialization of your RDF graph, because there are lots of different

I am working on an application using apache jena, to access dbpedia using sparql. Well I am very new to DBPedia and apache jena, I did some research and started with some sample code to create VCARD. public class DpPedia extends Object { static String personURI = "<!..http://def/JohnSmith..!>"; static String fullName = "John Smith"; static String Fullname = "Pulkit Gupta"; public static void main (String args[]) { // create an empty model Model model = ModelFactory.createDefaultModel(); // create the resource Resource johnSmith = model.createResource(personURI); Resource pulkitgupta=model

CONSTRUCT is an alternative SPARQL result clause to SELECT . Instead of returning a table of result values, CONSTRUCT returns an RDF graph. For instance, running this query in the following Java code produces an HttpException: 406 Unacceptable . But if instead of the CONSTRUCT block, I choose SELECT ?x , it's just fine. Does Jena support CONSTRUCT , and if so, how? Both queries are acceptable to the DBpedia endpoint . PREFIX : <http://dbpedia.org/resource/> PREFIX onto: <http://dbpedia.org/ontology/> CONSTRUCT { :France onto:anthem ?x } WHERE { :France onto:anthem ?x . } Query query =

I am a beginner to SPARQL and was wondering if there was a query which could help me return transitive relations. For example the n3 file below I would want a query that would return "a is the sameas c" or something along those lines. Thanks @prefix : <http://websitename.com/links/> . @prefix owl: <http://www.w3.org/2002/07/owl#> . :a owl:sameas :b. :b owl:sameas :c. You can use property paths if you are using a suitably enabled SPARQL 1.1 engine, you've tagged your question Jena so I assume you are using its ARQ engine which supports this feature. So you can write a query like the following: