hibernate问题再求解

Question

这是较详细的代码DAOImp类代码import java.util.List;
import model.Student;
import org.hibernate.HibernateException;
import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.Transaction;
import BusinessManager.BM;public class DAOImp {
    static Session session=null;
        
        /*------------取得所有的学生列表-----------------*/
        public static List getAllStu() {
                List list=null;
                try {
                        session = HibernateUtil.currentSession(); //开启连接
                        Transaction tx = session.beginTransaction(); //开启事务
                        Query q=session.createQuery("from Student");
                        list=q.list();
                        tx.commit();                } catch (HibernateException e) { //捕捉例外
                        e.printStackTrace();
                }finally
                {
                        HibernateUtil.closeSession(session);//!!!!!!!!第71行
                }
                return list;        }
}HibernateUtil类代码
public class HibernateUtil {
  private static final SessionFactory sessionFactory;  static {
        try {
            sessionFactory = new Configuration().configure()
                    .buildSessionFactory();
        } catch (HibernateException ex) {
            throw new RuntimeException("Exception building SessionFactory: "
                    + ex.getMessage(), ex);
        }
    }    public static Session currentSession() throws HibernateException {
        Session s = sessionFactory.openSession();
        return s;
    }    public static void closeSession(Session s) {
        s.close();
    }}

Answer 1

不要Rebuild,一Rebuild就相当于把内存中保存的信息给清掉了，这样当然会保错，应该make