JSP做的页面部署到服务器的TOMCAT之后就崩了？？求大神指导

[jarcem]

在下是一名应届生，做毕业设计时发现的这个问题
我在本地测试的时候一切正常,JSTL啊什么的都能正常用
但是我部署到自己租的那台服务器之后页面就出现了问题
目前排除了数据库的访问问题
预计问题范围在session和jstl部分，但是无法证实，求大佬


这是登录验证的servlet

public class UserLoginServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        super.doGet(req, resp);
    }

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        resp.setContentType("text/html; charset=utf-8;");
        req.setCharacterEncoding("UTF-8");
        resp.setCharacterEncoding("UTF-8");
        PrintWriter printWriter = resp.getWriter();
        HttpSession session = req.getSession();
        UserInfoBeanServices userInfoBeanServices = new UserInfoBeanServicesImp();
        UserInfoBean userInfoBean = new UserInfoBean();
        userInfoBean.setUse_id(req.getParameter("username"));
        userInfoBean.setUse_password(req.getParameter("password"));
        if (StringUtil.isNotNull(userInfoBean.getUse_id()) && StringUtil.isNotNull(userInfoBean.getUse_password())) {
            if (userInfoBeanServices.loginCheck(userInfoBean.getUse_id(), userInfoBean.getUse_password()) == 1) {
                userInfoBean = userInfoBeanServices.getUserInfo(userInfoBean.getUse_id());
                session.setAttribute("uib", userInfoBean);
                req.getRequestDispatcher("/mainPage").forward(req, resp);
            } else {
                printWriter.println("<script>alert('登录失败');history.back();</script>");
            }
        }
    }
}

以下为负责侧边菜单栏跳转的servlet

public class MainPageServlet extends HttpServlet {

    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        super.doGet(req, resp);
    }

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        resp.setContentType("text/html; charset=utf-8;");
        req.setCharacterEncoding("UTF-8");
        resp.setCharacterEncoding("UTF-8");
        PrintWriter printWriter = resp.getWriter();
        HttpSession session = req.getSession();
        String param = null;
        UserInfoBean userInfoBean = (UserInfoBean) session.getAttribute("uib");
        switch (userInfoBean.getUse_type()){
            case "student":param="/pages/stuPages/";break;
            case "teacher":param="/pages/teaPages/";break;
            case "admin":param="/pages/admPages/";break;
        }
        param+="leftMainMenu.jsp";
        req.setAttribute("leftmenuurl", param);
        req.getRequestDispatcher("/pages/main.jsp").forward(req, resp);
    }
}

前端页面部分的关键代码

<iframe frameborder="0" id="leftMenu" scrolling="auto" src="${leftmenuurl}" style="height: 720px; width: 170px;"></iframe>

public class UserInfoServlet extends HttpServlet {
    private HttpSession session = null;
    private UserInfoBeanServices userInfoBeanServices = null;
    private UserInfoBean userInfoBean = null;
    private PrintWriter printWriter = null;

    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        resp.setContentType("text/html; charset=utf-8");
        resp.setCharacterEncoding("UTF-8");
        req.setCharacterEncoding("UTF-8");
        PrintWriter printWriter = resp.getWriter();
        session = req.getSession();
        userInfoBean = (UserInfoBean) session.getAttribute("uib");
        req.setAttribute("usb", userInfoBean);
        req.getRequestDispatcher("/pages/userInfo.jsp").forward(req, resp);
    }

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        resp.setContentType("text/html; charset=utf-8");
        resp.setCharacterEncoding("UTF-8");
        req.setCharacterEncoding("UTF-8");
        printWriter = resp.getWriter();
        session = req.getSession();
        userInfoBeanServices = new UserInfoBeanServicesImp();
        userInfoBean = (UserInfoBean) session.getAttribute("uib");
        Enumeration<String> e = req.getParameterNames();
        String paramName = null;
        while (e.hasMoreElements()){
            paramName = e.nextElement();
            switch (paramName){
                case "newtelephone":{
                    if (StringUtil.isNotNull(req.getParameter(paramName))){
                        userInfoBean.setUse_telephone(req.getParameter(paramName));
                        int result = userInfoBeanServices.updateUser(userInfoBean);
                        printWriter.println("<script>alert('修改"+(result==1?"成功":"失败")+"');"+(result==1?"location.href='/userInfo';target='mainWindow'":"history.back();")+"</script>");
                    }else{
                        printWriter.println("<script>alert('新号码不能为空');</script>");
                    }
                };break;
                case "oldpassword":{
                    if (StringUtil.isNotNull(req.getParameter(paramName)) && userInfoBean.getUse_password().equals(req.getParameter(paramName))){
                        if (!userInfoBean.getUse_password().equals(req.getParameter("newpassword"))){
                            if (StringUtil.isNotNull(req.getParameter("newpassword"))){
                                userInfoBean.setUse_password(req.getParameter("newpassword"));
                                int result = userInfoBeanServices.updateUser(userInfoBean);
                                printWriter.println("<script>alert('修改"+(result==1?"成功":"失败")+"');"+(result==1?"location.href='/userInfo';target='mainWindow'":"history.back();")+"</script>");
                            }else{
                                printWriter.println("<script>alert('新密码不能为空');history.back();</script>");
                            }
                        }else{
                            printWriter.println("<script>alert('新密码不能与原密码相同');history.back();</script>");
                        }
                    }else{
                        printWriter.println("<script>alert('原密码错误');history.back();</script>");
                    }
                };break;
            }
        }
    }
}

<html>

<body>
<div class="pageBox" style="width: 100%;height: 800px; text-align: center;">
    <p class="pageBoxTitle"><label>个人信息</label></p>
    <div style="margin: 10px;">
        <div class="pageBox" style="text-align: center;height: 207px; width: 146px;"></div>
        <div class="list-group" style="margin-top: 10px;">
            <a class="list-group-item disabled" style="text-align: center;">${usb.use_id}</a>
            <a name="uname" class="list-group-item disabled" style="text-align: center;">${usb.use_name}</a>
            <a name="usex" class="list-group-item disabled" style="text-align: center;">${usb.use_sex}</a>
            <a name="utype" class="list-group-item disabled" style="text-align: center;">${usb.use_type}</a>
            <button name="utel" type="button" class="list-group-item" style="text-align: center;" data-toggle="modal"
                    data-target="#telModal">${usb.use_telephone}</button>

            <div class="modal fade" id="telModal" tabindex="-1" role="dialog">
                <div class="modal-dialog" role="document">
                    <div class="modal-content">
                        <form id="updTel" action="userInfo" method="post">
                            <div class="modal-header">
                                <button type="button" class="close" data-dismiss="modal" aria-label="Close"><span
                                        aria-hidden="true">×</span></button>
                                <h4 class="modal-title">修改电话号码</h4>
                            </div>
                            <div class="modal-body">
                                <input style="width: 70%;" name="newtelephone" placeholder="请输入新的电话号码" value=""/>
                            </div>
                            <div class="modal-footer">
                                <button type="button" class="btn btn-default" data-dismiss="modal">关闭</button>
                                <button type="button" onclick="$('#updTel').submit()" class="btn btn-primary">保存</button>
                            </div>
                        </form>
                    </div>
                    <!-- /.modal-content -->
                </div>
                <!-- /.modal-dialog -->
            </div>
            <!-- /.modal -->
            <button type="button" class="list-group-item" style="text-align: center;" data-toggle="modal"
                    data-target="#pwdModal">密码不可见
            </button>

            <div class="modal fade" id="pwdModal" tabindex="-1" role="dialog">
                <div class="modal-dialog" role="document">
                    <div class="modal-content">
                        <div class="modal-header">
                            <button type="button" class="close" data-dismiss="modal" aria-label="Close"><span
                                    aria-hidden="true">×</span></button>
                            <h4 class="modal-title">修改密码</h4>
                        </div>
                        <form id="updPwd" action="userInfo" method="post">
                        <div class="modal-body">

然而实际部署到服务器之后侧边栏部分提示
HTTP Status 404 – Not Found
Type Status Report

Message /$%7Bleftmenuurl%7D

Description The origin server did not find a current representation for the target resource or is not willing to disclose that one exists.

Apache Tomcat/7.0.91

个人信息页面部分则直接显示了${usb.use_id}等字段样式，求助各位大神