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Location: / Dashboard / Main / VirtJenaSPARQLExample2

import com.hp.hpl.jena.query.*;
import com.hp.hpl.jena.rdf.model.RDFNode;

import virtuoso.jena.driver.*;

public class VirtuosoSPARQLExample2 {

	/**
	 * Executes a SPARQL query against a virtuoso url and prints results.
	 */
	public static void main(String[] args) {

		String url;
		if(args.length == 0)
		    url = "jdbc:virtuoso://localhost:1111";
		else
		    url = args[0];

/*			STEP 1			*/
		VirtGraph graph = new VirtGraph ("Example2", url, "dba", "dba");

/*			STEP 2			*/
/*		Load data to Virtuoso		*/
		graph.clear ();

		System.out.print ("Begin read from 'http://www.w3.org/People/Berners-Lee/card#i'  ");
		graph.read("http://www.w3.org/People/Berners-Lee/card#i", "RDF/XML");
		System.out.println ("\t\t\t Done.");

		System.out.print ("Begin read from 'http://demo.openlinksw.com/dataspace/person/demo#this'  ");
		graph.read("http://demo.openlinksw.com/dataspace/person/demo#this", "RDF/XML");
		System.out.println ("\t Done.");

		System.out.print ("Begin read from 'http://kidehen.idehen.net/dataspace/person/kidehen#this'  ");
		graph.read("http://kidehen.idehen.net/dataspace/person/kidehen#this", "RDF/XML");
		System.out.println ("\t Done.");


/*			STEP 3			*/
/*		Select only from VirtGraph	*/
		Query sparql = QueryFactory.create("SELECT ?s ?p ?o WHERE { ?s ?p ?o }");

/*			STEP 4			*/
		VirtuosoQueryExecution vqe = VirtuosoQueryExecutionFactory.create (sparql, graph);

		ResultSet results = vqe.execSelect();
		while (results.hasNext()) {
			QuerySolution result = results.nextSolution();
		    RDFNode graph_name = result.get("graph");
		    RDFNode s = result.get("s");
		    RDFNode p = result.get("p");
		    RDFNode o = result.get("o");
		    System.out.println(graph_name + " { " + s + " " + p + " " + o + " . }");
		}

		System.out.println("graph.getCount() = " + graph.getCount());
	}
}
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