my Tema Resource

package com.ipn.escom.testerRest.resources;

import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;

import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;
import javax.ws.rs.core.Context;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.Request;
import javax.ws.rs.core.UriInfo;

import com.ipn.escom.testerRest.db.Connector;
import com.ipn.escom.testerRest.modelo.Tema;

@Path("/temas")
public class TemaResource {
    @Context
    UriInfo uriInfo;
    @Context
    Request request;

    private Connector conn;

    @GET
    @Produces({MediaType.APPLICATION_XML, MediaType.APPLICATION_JSON})
    public List<Tema> getTemas() throws SQLException{
        conn=new Connector();
        List<Tema> temas=new ArrayList<Tema>();
        String selTemas="select * from temas;";
        ResultSet rs= conn.ejecutarSelect(selTemas);
        while(rs.next()){
            Integer id=rs.getInt("id_tema");
            String nb = rs.getString("nb_tema");
            String ds = rs.getString("ds_tema");
            temas.add(new Tema(id, nb, ds));
        }
        conn.terminarSesion();

        return temas;
    }
}