package auction.dao.hibernate;import auction.dao.*;import auction.model.*;import org.apache.commons.logging.Log;import org.apache.commons.logging.LogFactory;/** * Returns Hibernate-specific instances of DAOs. * <p/> * If for a particular DAO there is no additional non-CRUD functionality, we use * a nested static class to implement the interface in a generic way. This allows clean * refactoring later on, should the interface implement business data access * methods at some later time. Then, we would externalize the implementation into * its own first-level class. * * @author Christian Bauer */public class HibernateDAOFactory extends DAOFactory {    private static Log log = LogFactory.getLog(HibernateDAOFactory.class);    public ItemDAO getItemDAO() {        return (ItemDAO)instantiateDAO(ItemDAOHibernate.class);    }    public CategoryDAO getCategoryDAO() {        return (CategoryDAO)instantiateDAO(CategoryDAOHibernate.class);    }    public CommentDAO getCommentDAO() {        return (CommentDAO)instantiateDAO(CommentDAOHibernate.class);    }    public UserDAO getUserDAO() {        return (UserDAO)instantiateDAO(UserDAOHibernate.class);    }    public CategorizedItemDAO getCategorizedItemDAO() {        return (CategorizedItemDAO)instantiateDAO(CategorizedItemDAOHibernate.class);    }    public BillingDetailsDAO getBillingDetailsDAO() {        return (BillingDetailsDAO)instantiateDAO(BillingDetailsDAOHibernate.class);    }    public ShipmentDAO getShipmentDAO() {        return (ShipmentDAO)instantiateDAO(ShipmentDAOHibernate.class);    }    private GenericHibernateDAO instantiateDAO(Class daoClass) {        try {            log.debug("Instantiating DAO: " + daoClass);            return (GenericHibernateDAO)daoClass.newInstance();        } catch (Exception ex) {            throw new RuntimeException("Can not instantiate DAO: " + daoClass, ex);        }    }    // Inline concrete DAO implementations with no business-related data access methods.    // If we use public static nested classes, we can centralize all of them in one source file.    public static class CategorizedItemDAOHibernate            extends GenericHibernateDAO<CategorizedItem, CategorizedItem.Id>            implements CategorizedItemDAO {}    public static class CommentDAOHibernate            extends GenericHibernateDAO<Comment, Long>            implements CommentDAO {}    public static class ShipmentDAOHibernate            extends GenericHibernateDAO<Shipment, Long>            implements ShipmentDAO {}}