Hi Vestal, Thank you for your reply. I used the method of ResultSetFormatter "out(OutputStream out, ResultSet resultSet, Prologue prologue)" listed in the javadoc. Here is the link: https://jena.apache.org/documentation/javadoc/arq/org.apache.jena.arq/org/apache/jena/query/ResultSetFormatter.html Class Query is the subclass of Class Prologue, so I think it could be used in this way.
Best regards, Pan On Tue, Mar 12, 2024 at 1:30 PM Steve Vestal <[email protected]> wrote: > Which line of this code is raising the exception? When I look at the > ResultSetFormatter API online, I see 9 signatures for the out method, > only 2 of which have three parameters, where the third parameter is a > PrefixMapping or Prologue but not a Query. The only one with a Query > parameter is "static void > out(ResultSet qresults, Query query)" (the javadoc doesn't explicitly > say where the output goes). If the exception occurs there, you could > try one of the other PrefixMapping.out methods to see if that avoids the > exception. > > On 3/12/2024 1:13 AM, Lorenz Buehmann wrote: > > Hi, > > > > how did you setup your project? Which Jena version? Do you use Maven? > > Which dependencies? It looks like ARQ.init() hasn't been called which > > should happen automatically if the setup of the project is correct. > > > > > > Cheers, > > Lorenz > > > > On 11.03.24 14:44, Anna P wrote: > >> Dear Jena support team, > >> > >> Currently I just started to work on a SPARQL project using Jena and I > >> could > >> not get a solution when I query a model. > >> I imported a turtle file and ran a simple query, and the snippet code is > >> shown below. However, I got the error. > >> > >> public class App { > >> public static void main(String[] args) { > >> try { > >> Model model = RDFDataMgr.loadModel('data.ttl', > >> Lang.TURTLE); > >> RDFDataMgr.write(System.out, model, Lang.TURTLE); > >> String queryString = "SELECT * { ?s ?p ?o }"; > >> Query query = QueryFactory.create(queryString); > >> QueryExecution qe = QueryExecutionFactory.create(query, > >> model); > >> ResultSet results = qe.execSelect(); > >> ResultSetFormatter.out(System.out, results, query); > >> qe.close(); > >> } catch (Exception e) { > >> e.printStackTrace(); > >> } > >> } > >> } > >> > >> Here is the error message: > >> > >> org.apache.jena.riot.RiotException: Not registered as a SPARQL result > >> set > >> output syntax: Lang:SPARQL-Results-JSON > >> at > >> > org.apache.jena.sparql.resultset.ResultsWriter.write(ResultsWriter.java:179) > > >> > >> at > >> > org.apache.jena.sparql.resultset.ResultsWriter.write(ResultsWriter.java:156) > > >> > >> at > >> > org.apache.jena.sparql.resultset.ResultsWriter.write(ResultsWriter.java:149) > > >> > >> at > >> > org.apache.jena.sparql.resultset.ResultsWriter$Builder.write(ResultsWriter.java:96) > > >> > >> at > >> > org.apache.jena.query.ResultSetFormatter.output(ResultSetFormatter.java:308) > > >> > >> at > >> > org.apache.jena.query.ResultSetFormatter.outputAsJSON(ResultSetFormatter.java:516) > > >> > >> at de.unistuttgart.ki.esparql.App.main(App.java:46) > >> > >> > >> Thank you for your time and help! > >> > >> Best regards, > >> > >> Pan > >> >
