Jena and DateTime

TestDateTime.java

package testjena;

import static org.junit.Assert.*;
import org.junit.Test

import org.junit.Before;

import com.hp.hpl.jena.query.ResultSetFormatter;

import com.hp.hpl.jena.query.Query;
import com.hp.hpl.jena.query.QueryExecution;
import com.hp.hpl.jena.query.QueryExecutionFactory;
import com.hp.hpl.jena.query.QueryFactory;
import com.hp.hpl.jena.query.ResultSet;
import com.hp.hpl.jena.rdf.model.Literal;
import com.hp.hpl.jena.rdf.model.Model;
import com.hp.hpl.jena.rdf.model.ModelFactory;
import com.hp.hpl.jena.rdf.model.Property;
import com.hp.hpl.jena.rdf.model.Resource;
import com.hp.hpl.jena.query.QuerySolution;
import com.hp.hpl.jena.rdf.model.RDFNode;

class TestDateTime {

    @Test
    public void testJenaDateTime() {

	Model model = ModelFactory.createDefaultModel();
	Resource resource = model.createResource("http://example.com/resource/test");
	Property property = model.createProperty("http://example.com/prop/test");
	Calendar cal = GregorianCalendar.getInstance();
	Literal value = model.createTypedLiteral(cal);
	resource.addProperty(property, value);

        /**
         * Results in:
         *
         * Subject:   <http://example.com/resource/test> 
         * Predicate: <http://example.com/prop/test>
         * Object:    "2011-06-04T19:16:58.869Z"^^<http://www.w3.org/2001/XMLSchema#dateTime>
         *
         */

        /**
         * First, let's use ARQ to retrieve the date via a SPARQL query
         */

        String sparql = "SELECT ?s ?p ?o WHERE { ?s ?p ?o }";
		

	Query query = QueryFactory.create(sparql);
	QueryExecution qe = QueryExecutionFactory.create(query, model);
		

	Date result;
	try {

		ResultSet rs = qe.execSelect();
		for ( ; rs.hasNext(); ) {
			QuerySolution sol = rs.nextSolution();
			RDFNode resultNode = sol.get("o");
			// traverse the to the date - must be careful you know what you want
			// as if these aren't types as dateTime, you'll wind up with nulls to check
			result = resultNode.asLiteral().getValue().asCalendar().getTime()
		}
	}
	finally {
	   qe.close();
	}
	
	System.out.println("Resulting date: " + result);
        
        /**
         * Now let's try that again, but with using the Jena Model API
         */

	Statement stmt = resource.getProperty(property);
	Literal resultLiteral = stmt.getLiteral();
	Date resultDate = resultLiteral.getValue().asCalendar().getTime();

        assertEquals(resultDate, result);
    }


}