VOS.VirtJenaSPARQLExample8

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  • VOS.VirtJenaSPARQLExample8(Last) -- DAVWikiAdmin? , 2018-11-24 15:52:19 Edit WebDAV System Administrator 2018-11-24 11:52:19

    import org.apache.jena.query.*;
    import org.apache.jena.rdf.model.RDFNode;
    
    import virtuoso.jena.driver.*;
    
    public class VirtuosoSPARQLExample8 {
    
    	/**
    	 * 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 set = new VirtGraph (url, "dba", "dba");
    
    /*			STEP 2			*/
    System.out.println("\nexecute: CLEAR GRAPH <http://test1>");
                    String str = "CLEAR GRAPH <http://test1>";
                    VirtuosoUpdateRequest vur = VirtuosoUpdateFactory.create(str, set);
                    vur.exec();                  
    
    System.out.println("\nexecute: INSERT INTO GRAPH <http://test1> { <aa> <bb> 'cc' . <aa1> <bb1> 123. }");
                    str = "INSERT INTO GRAPH <http://test1> { <aa> <bb> 'cc' . <aa1> <bb1> 123. }";
                    vur = VirtuosoUpdateFactory.create(str, set);
                    vur.exec();                  
    
    /*			STEP 3			*/
    /*		Select all data in virtuoso	*/
    System.out.println("\nexecute: SELECT * FROM <http://test1> WHERE { ?s ?p ?o }");
    		Query sparql = QueryFactory.create("SELECT * FROM <http://test1> WHERE { ?s ?p ?o }");
    
    /*			STEP 4			*/
    		QueryExecution vqe = VirtuosoQueryExecutionFactory.create (sparql, set);
    
    		ResultSet results = vqe.execSelect();
    		while (results.hasNext()) {
    			QuerySolution rs = results.nextSolution();
    		    RDFNode s = rs.get("s");
    		    RDFNode p = rs.get("p");
    		    RDFNode o = rs.get("o");
    		    System.out.println(" { " + s + " " + p + " " + o + " . }");
    		}
    
    
    System.out.println("\nexecute: DELETE FROM GRAPH <http://test1> { <aa> <bb> 'cc' }");
                    str = "DELETE FROM GRAPH <http://test1> { <aa> <bb> 'cc' }";
                    vur = VirtuosoUpdateFactory.create(str, set);
                    vur.exec();                  
    
    System.out.println("\nexecute: SELECT * FROM <http://test1> WHERE { ?s ?p ?o }");
    		vqe = VirtuosoQueryExecutionFactory.create (sparql, set);
                    results = vqe.execSelect();
    		while (results.hasNext()) {
    			QuerySolution rs = results.nextSolution();
    		    RDFNode s = rs.get("s");
    		    RDFNode p = rs.get("p");
    		    RDFNode o = rs.get("o");
    		    System.out.println(" { " + s + " " + p + " " + o + " . }");
    		}
    
    	
    	}
    }