org.apache.jasper.JasperException: An exception occurred processing JSP page /Left.jsp at line 20

17:                     <td height="5" align="center"><img src="Images/ic.gif" width="1" height="1"></td>
18:                 </tr>
19:                 <%
20:                     if (session.getAttribute("type").toString().equals("1")) {
21:                 %>
22:                 <tr>
23:                     <td height="30" align="center" background="Images/left2.jpg" style="text-align: left; padding-left: 40px;"><a href="TeacherManager.action">XXX</a></td>

这个项目原来是用struts2写的，我加入了Hibernate.出现了这个错误，下面是action的对应代码
public String execute() throws Exception {
        if (Type.equals("系统管理员")) {
            String hql = "from Admin where Admin_Username=''" + Username + "and Admin_Password=''" + Password;
            if (null == new BaseDaoImpl().CheckLogin(hql)) {
                Msg = "用户名或者密码错误";
                return INPUT;
            } else {
                // 获取ID
                String Admin_ID = new BaseDaoImpl().CheckLogin(hql);
                // 创建session
                ServletActionContext.getRequest().getSession().setAttribute("id", Admin_ID);
                ServletActionContext.getRequest().getSession().setAttribute("type", "1");
                return SUCCESS;
            }