如何将JENA Sparql Query ResultSet保存为JSON？

Question

How do I store the JENA ResultSet as JSON formatted string? I'm currently only able to get the ResultSet to output to the System.out console, but I can't save that to a java String. This is an example of where I'm at:

QueryExecution qexec = QueryExecutionFactory.sparqlService(endpoint, query);
ResultSet results = qexec.execSelect();
// the following prints out JSON in the System.out console:
ResultSetFormatter.outputAsJSON(System.out, results);
// but how do I save it as a String?
// ie.  
String json = ResultSetFormatter.outputAsJSON(System.out, results);
// obviously that doesn't work, but how would one get the equivalent working version?

I want to be able to send the JSON variable to another method to perform some work on it.

Thanks in advance!

Answer 1

Try writing to a ByteArrayOutputStream and converting the bytes from that to a String

QueryExecution qexec = QueryExecutionFactory.sparqlService(sparqlEndpointQuery, query);
ResultSet results = qexec.execSelect();

// write to a ByteArrayOutputStream
ByteArrayOutputStream outputStream = new ByteArrayOutputStream();

ResultSetFormatter.outputAsJSON(outputStream, results);

// and turn that into a String
String json = new String(outputStream.toByteArray());

System.out.println(json);