Sending non-standard SPARQL queries with Apache Jena

Some non-standard extensions of SPARQL results in queries that are not syntactically compliant with SPARQL specifications. An example of such an extension is the Virtuoso full text search that uses a “magic” prefix bif without defining it in the query.

When using non-compliant extension in Apache Jena, a call to QueryExecutionFactory.sparqlService will fail. A workaround that worked for me is to use QueryEngineHTTP class as in:

  QueryEngineHTTP qExec = new QueryEngineHTTP(sparqlEndpointUrl, sparql);
  ResultSet res = qExec.execSelect();
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