Hibernate - The way Hibernate 3 use the native Query

Step 1: define the pojo and NamedQueries, e.g.
@Entity
@NamedQueries({
            @NamedQuery(name = "findEmployeeByEmail", query = "select myEmployee from Employee myEmployee where myEmployee.email = ?1"),  
….
@NamedQuery(name = "updateEmployeeByCity",
            query = "UPDATE Employee e " +
                    "SET e.address.city = :newCity " +
                    "WHERE e.address.city = :oldCity")

@Table(schema = "CLASSICCARS", name = "EMPLOYEE")
@XmlAccessorType(XmlAccessType.FIELD)
@XmlType(namespace = "MySpring2/com/tantalus/domain", name = "Employee")
public class Employee implements Serializable {
      private static final long serialVersionUID = 1L;
…..}

Step 2: use it in the DAO implement,  e.g.

/**
* DAO to manage Employee entities.
*
 */
@Repository("EmployeeDAO")
@Transactional
public class EmployeeDAOImpl extends AbstractJpaDao<Employee> implements
            EmployeeDAO {
….
      @SuppressWarnings("unchecked")
      @Transactional
      public Set<Employee> findEmployeeByEmail(String email) throws DataAccessException {
            Query query = getEntityManager().createNamedQuery("findEmployeeByEmail", email);
            return new LinkedHashSet<Employee>(query.getResultList());
      }

    
     @SuppressWarnings("unchecked")
      @Transactional
      public void updateEmployeeByCity(String newCity,String oldCity) throws DataAccessException {
            Query query = entityManager.createNamedQuery("updateCustomersByCity");
query.setParameter("oldCity", " oldCity ");
query.setParameter("newCity", " newCity ");
query.executeUpdate();
   }
….
}