public class StudentDao  extends Studentservice{
     @Override
    public void saveStudent(Student stu ){
    	 	Session session=HibernateUtils.openSession();
    	 	Transaction tr=session.beginTransaction();
    	 	session.save(stu);//使用session保存对象
    	 	tr.commit();
    	 	session.close();
     }
     @Override
    public List<Student> queryAllEmp() {
    	 Session session=HibernateUtils.openSession();
    	 Transaction tr=session.beginTransaction();
    	 Query query=session.createQuery("from Student");
    	 //查询全部
    	 List<Student> list=query.list();
    	 System.out.println(list);
    	 tr.commit();//提交事务
    	 return list;
    	 }
    @Override
    public List<Student> select(int id) {//重要的查询，返回list,可以多重查询，完全的面向对象
    	 Session session=HibernateUtils.openSession();
    	 Transaction tr=session.beginTransaction();
    	Criteria criteria = session.createCriteria(Student.class);
        criteria.add(Restrictions.eq("id", id));//里面的id是类中的属性
        //criteria.add(Restrictions.eq("name", %杨%));//模糊查询，含有杨的用户
        List<Student> list = criteria.list();
        System.out.println(list);
        return list;
    }
    public void updateStudent(Student  stu){
    	Session session=HibernateUtils.openSession();
     	Transaction tr=session.beginTransaction();
     	//使用session保存对象
        session.update(stu);
        System.out.println(stu);
     	tr.commit();
     	session.close();
    }
    public void deleteStudent(int id) {
    	Session session=HibernateUtils.openSession();
     	Transaction tr=session.beginTransaction();
     	  Student Stu = session.load(Student.class,id);
         //System.out.println(id);
     	session.delete(Stu);
      	tr.commit();
      	session.close();
    }