I have a class BaseDAO as bellow and I am getting NullPointerException on
EntityManager em = emf.createEntityManager(); line from BaseDAO class, Can
someone help me how to fix it?
public class BaseDAO<T> {
@PersistenceUnit(unitName = "citespacePU")
EntityManagerFactory emf;
public List<T> ListCountry(){
EntityManager em = emf.createEntityManager();
try{
Query q = em.createQuery("Select c from Country c ");
List<Country> c = q.getResultList();
return (List<T>) c;
}finally{
if (em != null && em.isOpen()) {
em.close();
}
}
}
}
I have my Jersey resource class:
@Path("/user/")
public class UserResource {
@GET
@Produces("text/plain")
public String registerUser(){
BaseDAO<Country> countryDAO = new BaseDAO<Country>();
List<Country> c = countryDAO.ListCountry();
String y = "";
for(Country x: c){
y = y + ":" +x.getName();
}
return "[Country List]:"+y;
}
--
Atenciosamente,
Roan Brasil Monteiro
http://roanbrasil.wordpress.com/