Qu'est-ce qui cause cette erreur Java "Impossible de trouver le symbole"?

Je modifie le code hérité et je continue à obtenir une erreur bizarre "Impossible de trouver le symbole" qui me jette. XXX PRE>

Peer de voiture: P>

   package fr.dao;
    import fr.model.accounting.Cost;
    import fr.model.company.Car;

    public class CompanyDAO extends GenericDAO<Company> {

    private enum ChildType {
    COST{
    public void addChildToCompany(Company company, Object child) {
    company.addCost((Cost)child);
    }
    },
    CAR{
    public void addChildToCompany(Company company, Object child) {
    company.addCar((Car)child);
    }
    };
    public abstract void addChildToCompany(Company company, Object child);
    }
private void addChildToCompany(Long idCompany, Object child, ChildType type) throws NotFoundDAOException, AlreadyExistDAOException, Exception {
        try {
            // Begin unit of work
            Session session = HibernateUtil.getSessionFactory().getCurrentSession();
            session.beginTransaction();

            Company company = (Company) session.load(Company.class, idCompany);

            type.addChildToCompany(company, child);
            session.flush();

            // End unit of work
            session.getTransaction().commit();

        } catch (ObjectNotFoundException ex) {
            HibernateUtil.getSessionFactory().getCurrentSession().getTransaction().rollback();
            throw new NotFoundDAOException("Identified object " + idCompany
                    + " doesn't exist in database", ex);
        } catch (ConstraintViolationException ex) {
            HibernateUtil.getSessionFactory().getCurrentSession().getTransaction().rollback();
            throw new AlreadyExistDAOException("The new identity already exsits in database", ex);
        } catch (Exception ex) {
            ex.printStackTrace();
            HibernateUtil.getSessionFactory().getCurrentSession().getTransaction().rollback();
            throw new Exception(ex);
        }
    }
    public CompanyDAO() {
    super(Company.class);
    }
    public void addCarToCompany(Long idCompany, Car car) throws NotFoundDAOException, AlreadyExistDAOException, Exception {
    addChildToCompany(idCompany, car, ChildType.CAR);
    }
    }