# AGJenaQueryExecution.java

`package com.franz.agjena.examples;
import com.franz.agbase.AllegroGraphException;
import com.franz.agbase.AllegroGraph;
import com.franz.agbase.AllegroGraphConnection;
import com.franz.agbase.examples.AGPaths;
import com.franz.agjena.AllegroGraphGraphMaker;
import com.franz.agjena.AllegroGraphModel;
import com.franz.agjena.query.AllegroGraphQueryExecutionFactory;
import com.hp.hpl.jena.graph.Graph;
import com.hp.hpl.jena.query.QueryExecution;
import com.hp.hpl.jena.query.QuerySolution;
import com.hp.hpl.jena.query.ResultSet;
import com.hp.hpl.jena.rdf.model.Model;
import com.hp.hpl.jena.rdf.model.RDFNode;
import com.hp.hpl.jena.rdf.model.Resource;
import com.hp.hpl.jena.vocabulary.DC;
public class AGJenaQueryExecution {
/**
* Demonstrates QueryExecution
*
* @param args unused
* @throws AllegroGraphException
*/
public static void main(String[] args) throws AllegroGraphException {
// Connect to server, which must already be running.
AllegroGraphConnection ags = new AllegroGraphConnection();
try {
ags.enable();
} catch (Exception e) {
throw new AllegroGraphException("Server connection problem", e);
}
// Create a fresh triple store
AllegroGraph ts = ags.renew("jenatest2", AGPaths.TRIPLE_STORES);
// Create a Graph maker for the store, and work in the default graph
AllegroGraphGraphMaker maker = new AllegroGraphGraphMaker(ts);
Graph graph = maker.getGraph();
Model model = new AllegroGraphModel(graph);
// Add some data to the default graph
Resource r1 = model.createResource("http://example.org/book#1") ;
Resource r2 = model.createResource("http://example.org/book#2") ;
r1.addProperty(DC.title, "SPARQL - the book")
.addProperty(DC.description, "A book about SPARQL");
r2.addProperty(DC.title, "Advanced techniques for SPARQL");
// A SPARQL query
String queryString =
"PREFIX dc: <" + DC.NS + ">\n" +
"SELECT ?title WHERE {?x dc:title ?title}" ;
// Run the query
QueryExecution qexec = AllegroGraphQueryExecutionFactory.create(queryString, model) ;
System.out.println("Titles: ") ;
try {
ResultSet rs = qexec.execSelect() ;
while(rs.hasNext()) {
QuerySolution rb = rs.nextSolution() ;
RDFNode x = rb.get("title") ;
System.out.println(" "+x) ;
}
} finally {
qexec.close() ;
}
// Close the triple store and disconnect from the server
ts.closeTripleStore();
ags.disable();
}
}
`

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