Problems when querying the SPARQL with Jena

[Anna P]

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