页面刷新白屏（跟踪后台代码无异常）

登录成功后页面正常显示。这时候再点次刷新就白屏
=====================Action =====================
public ActionForward showCampus(ActionMapping mapping, ActionForm form,
HttpServletRequest request, HttpServletResponse resp)
throws Exception {
try {
String imgUrl = HubConfig.getInstance().ImageAccessPath;
String activityPanel_fir=HubConfig.getInstance().ActivityPanle_Fir;
String activityPanel_sec=HubConfig.getInstance().ActivityPanle_Sec;
String theme = request.getParameter("theme");
showTitle(request,theme);
request.setAttribute("imgUrl", imgUrl);
request.setAttribute("theme", theme);
request.setAttribute("activityPanel_fir", activityPanel_fir);
request.setAttribute("activityPanel_sec", activityPanel_sec);
} catch (Exception e) {
logger.error("缓存获取异常!", e);
e.printStackTrace();
}

return forward(mapping,request,"campus");
}=====================================================================FILETER========================
public void doFilter(ServletRequest sRequest, ServletResponse sResponse,
FilterChain chain) throws IOException, ServletException {
HttpServletRequest request=(HttpServletRequest)sRequest;
HttpServletResponse response=(HttpServletResponse)sResponse;

if(null != request.getAttribute("hubFilterFlag")) {
chain.doFilter(request, response);
return;
}
request.setAttribute("hubFilterFlag", "1");
HttpSession session = request.getSession();
String requestURI = request.getRequestURI();
String info=UserVo.UserInfo;
UserVo userVo = null;
try{
userVo=(UserVo)session.getAttribute(info);}catch(Exception e){

}
// 判断登录状态，如果没登陆，直接跳转到登录页面，如果已登录，取得用户信息
if(null == session.getAttribute(UserVo.UserInfo)){
String tokenCode = request.getParameter(HubConfig.getInstance().tokenCode);
if(null == tokenCode || "".equals(tokenCode.trim())){
response.sendRedirect(HubConfig.getInstance().loginUrl);
return;
}
else{
// 根据 tokenCode 取得用户信息
userVo = Hessian.getUserInfo(tokenCode);
if(userVo == null){
response.sendRedirect(HubConfig.getInstance().loginUrl);
return;
}
userVo.setUa(getUserAgent(request));
userVo.setWapVersion("caiban");
session.setAttribute(UserVo.UserInfo, userVo);
}
initSession(request, response);
}
else{
String tokenCode = request.getParameter(HubConfig.getInstance().tokenCode);
if(tokenCode != null && !"".equals(tokenCode.trim())){
// 根据 tokenCode 取得用户信息
UserVo user = Hessian.getUserInfo(tokenCode);
if(user == null){
response.sendRedirect(HubConfig.getInstance().loginUrl);
return;
}
userVo.setWapVersion("caiban");
session.setAttribute(UserVo.UserInfo, user);
}
}

// 记录用户访问日志
//日志
SimpleDateFormat df = new SimpleDateFormat("yyyyMMdd HH:mm:ss SSS");
AccessLog access = AccessLog.getAccessLog(request);
if(access!=null && access.isNew() && userVo!=null) {
String r = requestURI!=null?requestURI.toLowerCase():"";
if(r.endsWith(".gif") || r.endsWith(".jpg") || r.endsWith(".css")
|| r.endsWith(".png") || r.endsWith(".bmp")) {
access = null;
}else {
access.setMsisdn(userVo.getPhoneNumber());
access.setUa(userVo.getUa());
access.setGateWapIP(request.getRemoteAddr());
access.setMobileIP(this.getMobileIP(request));
access.setReqBeginDate(df.format(new Date()));
access.setSrc(this.getReferer(request));
access.setUri(requestURI);
access.setUrl(request.getQueryString());
}
}
if(access!=null) {
access.setReqEndDate(df.format(new Date()));
access.info();
}
chain.doFilter(request, response);
}
=====================================================================JSP============================
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<%@page import="com.aspire.portal.hub.entity.TitleEntity"%>
<%@page import="com.aspire.portal.hub.dc.TitleDC"%>
<%@page import="com.aspire.portal.hub.dc.ContentDC"%>
<%@page import="com.aspire.portal.hub.entity.ContentEntity"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
String theme = (String)request.getAttribute("theme");
String activityPanel_sec=(String)request.getAttribute("activityPanel_sec");
String activityPanel_fir=(String)request.getAttribute("activityPanel_fir");
%>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<meta http-equiv="Cache-Control" content="no-cache"/>
<meta name="viewport" content="width=device-width; initial-scale=1.4;  minimum-scale=1.0; maximum-scale=2.0"/>
<meta name="MobileOptimized" content="240"/>
<link href="<%=basePath %>hubicity/css/css.css" type="text/css" rel="stylesheet"/>
<title>我的校园</title>
</head>

<body>
<div class="outside">
<div class="introbg">
<div class="titleimg"><img src="<%=basePath %>hubicity/image/logo.jpg" width="50" height="50"></div>
<div class="intro"><a class="introname strong">无线武汉</a> <a class="intronamered">我的校园</a><div class="margin_right margin_top margin_bottom xuline"></div>
【<a href="http://wap.hubeitd.cn:81/index.php?module=Page&func=Selectcity">切换</a>】    25～13℃</div>

</div>
<div class="clear"></div>
<div class="blueline"></div>
<div class="lightgray"><jsp:include page="title.jsp"></jsp:include></div>
<%if(!"".equals(activityPanel_fir)){ %>

<%} %><div class="clear"></div>

<%
List listTitle = (List)request.getAttribute("listTitle");
  %>

  <%
   List listCont = new ArrayList();
   int num = 0;
   for(int i = 0;i<listTitle.size();i++){
   num++;
   TitleEntity title = (TitleEntity)listTitle.get(i);
   %>

   <%
   if(num==3){
   System.out.println("NUM:"+num);
%>

<%if(!"".equals(activityPanel_sec)){ %>

<%} %>

<%
   }
   %>
<div class="strong crumb">【<%=title.getTitleName() %>】</div>

<div class="title">
<%
List titlesecond = TitleDC.getInstance().getTitlesByPid(title.getId());
int index = 0;
for(int j=0;j<titlesecond.size();j++){
index++;
TitleEntity titlesec = (TitleEntity)titlesecond.get(j);
%>
<a href="go.do?method=showDetails&id=<%=titlesec.getPid() %>&name=<%=title.getTitleName() %>&theme=<%=theme %>" ><%=titlesec.getTitleName() %></a>

<%
List listContent = ContentDC.getInstance().getContents(titlesec.getId());

for(int k=0;k<listContent.size()&&k<1;k++){
ContentEntity content = (ContentEntity)listContent.get(k);
listCont.add(content);
}
%>
<%
if(index%2==0&&index!=titlesecond.size()){
%>
</div><div class="title">

<%
}
}
%>
</div>
<div class="list">
<%

for(int n=0;n<listCont.size();n++){
ContentEntity ct = (ContentEntity)listCont.get(n);
%>
<img src="<%=basePath %>hubicity/image/dot2.gif" width="14" height="11" border="0" />
<a href="go.do?method=showContent&contentId=<%=ct.getContentId() %>&theme=<%=theme %>&name=<%=title.getTitleName() %>" ><%=ct.getContentTitle() %></a>
<br/>
<%
}
listCont.clear();
%>
</div>

<div class="clear"></div> <%
}
   %>

<div class="xuline margin10"></div>
<div class="list">
==所在位置==<br/>
<a href="http://wap.hubeitd.cn/">首页</a>>>我的校园<br/>
<a href="http://wap.hubeitd.cn:81/index.php?module=Page&func=Recommend">推荐</a>-<a href="http://wap.hubeitd.cn:81/index.php?module=Page&func=Option">留言</a>-<a href="http://wap.hubeitd.cn:81/index.php?module=Page&func=Help">帮助</a>-<a href="http://wap.hubeitd.cn:81/index.php?module=Page&func=Help&op=Book">存书签</a><br/>
<a class="copyright"><img src="<%=basePath %>hubicity/image/copyright.jpg" width="10" height="12" />无线城市[鄂ICP备10011758]</a>
</div>
</div>

</body>
</html>

==================================================
你没返回页面？？在execute()里，要返回的,return mapping.findForward("success");
但是你写的这个return forward(mapping,request,"campus")不知道对不对，我不是这样返回的
if(null != request.getAttribute("hubFilterFlag")) {
chain.doFilter(request, response);
return;
}

调试易

页面刷新白屏（跟踪后台代码无异常）

解决方案 »