Reading RDF file using jena

Question

Folks, I have been working on a project related to semantic web and I really need help right now as I am completely struck while reading RDF N-triples file of noble prize rdf dataset.

The dataset is taken from the below links.

Nobel prize rdf data description

I want to read name, gender, nationality, discipline and year from this N-triples rdf data file using jena and want to save it in turtle format.

I am able to read name and gender so far but struck while reading other attributes.

My java code is this:

package com.tausy.rdf.query;

import java.io.InputStream;

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.RDFNode;
import com.hp.hpl.jena.rdf.model.Resource;
import com.hp.hpl.jena.rdf.model.Statement;
import com.hp.hpl.jena.rdf.model.StmtIterator;
import com.hp.hpl.jena.util.FileManager;
import com.hp.hpl.jena.vocabulary.RDFS;

public class ParseNTripleRdf {

public static void main(String[] args) {
    String fileNameOrUri = "././Nobeldump.nt";
    Model model = ModelFactory.createDefaultModel();
    InputStream is = FileManager.get().open(fileNameOrUri);
    if (is != null) {
        model.read(is, null, "N-TRIPLE");
        //Resource person = model.getResource("http://xmlns.com/foaf/0.1/Person");

        //Property firstName = model.createProperty("http://xmlns.com/foaf/0.1/name");
        //String firstNameValue = person.getProperty(firstName).getString();
        //System.out.println(firstNameValue);
        modelStatements(model);
        //model.write(System.out, "TURTLE");
    } else {
        System.err.println("cannot read " + fileNameOrUri);
    }
}

public static void modelStatements(Model model){
    // list the statements in the Model
    StmtIterator iter = model.listStatements();

    // print out the predicate, subject and object of each statement
    while (iter.hasNext()) {
        Statement stmt      = iter.nextStatement();  // get next statement
        Resource  subject   = stmt.getSubject();     // get the subject
        Property  predicate = stmt.getPredicate();   // get the predicate
        RDFNode   object    = stmt.getObject();      // get the object

        // Create some properties in advance for convenience.
        final Property name = model.createProperty("http://xmlns.com/foaf/0.1/name");
        final Property gender = model.createProperty("http://xmlns.com/foaf/0.1/gender");
        final Property nationality = model.createProperty("http://dbpedia.org/ontology/country");
        final Property discipline = model.createProperty("http://data.nobelprize.org/terms/category");
        final Property year = model.createProperty("http://data.nobelprize.org/terms/year");

         //System.out.println("Subject: "+subject.getURI());
        //System.out.println("Predicate:  " + predicate.getLocalName());
        //System.out.println("Object:  " + object.toString());
        if (object instanceof Resource) {
            Resource res = (Resource)object;

            Statement s = res.getProperty(name);
            final String nameVal = s==null ? null : s.getString();

            s = res.getProperty(gender);
            final String genderVal = s==null ? null : s.getString();

            //s = res.getProperty(nationality);
            //final String nationalityVal = s==null ? null : s.getString();

            //s = res.getProperty(discipline);
            //final String disciplineVal = s==null ? null : s.getString();

            System.out.println(nameVal);
            System.out.println(genderVal);
            //System.out.println(nationalityVal);
            //System.out.println(disciplineVal);



        } else {
            // object is a literal
            System.out.print(" \"" + object.toString() + "\"");
        }
    } 

}

}

I want to query this turtle file to get simple information like:

• Find all the Nobel Laureates from the UK;
• Find all the Nobel Laureates who are female and were born after 1949;
• List all the Nobel Laureates ordering them by discipline for which they were awarded the prize. List the names in alphabetical order;
• Find all the Nobel Laureates born in the US who share the award with someone else;

Any kind of help would be highly appreciated. Thanks!