在jsp中会话超时后，如何重定向到登录页面？

Question

Hi i am developing application using struts and jsp. in jsp we are using Ajax calls , after session timeout, we are redirecting to log in page. but the problem is the log in page is displaying same div tag.i am checking user in session or not in javascript of jsp but always session have userid value, it never going to be null, if session expires also.

Answer 1

Two things

1. Configure a Welcome page as Login Page in web.xml
2. Create a filter and configure in web.xml , this should be the first filter in web.xml
3. In the filter check if the session is new the user should be guided to the login page , else the request should be processed.

Answer 2

Recently I made a tutorial about this exactly. Maybe it can be helpful. Is the same solution that abhi proposed but with an example.

http://classfoundexception.blogspot.com.es/2012/04/how-to-secure-struts-13-application.html

Answer 3

Every time the new request comes, you should check and validate session at server side. Also this timeout is handled by web server.Once time out is occurred, automatically server redirect user to session logout URL . You may change this configuration in conf files of server.

For more info see this

Answer 4

To handle Session Timeout/Expire for Ajax Call Request and to dispatch it to login page follows these steps.

1) In Your jsp wherever ajax function are written Set a header before your ajax send request.

req.open("POST", Servlet_PATH, true);
req.setRequestHeader("X-Requested-With", "XMLHttpRequest"); //set header
req.send();

2) In a Filter get the header like this and if session is null send as an Response Error

    httpRequest.getHeader("X-Requested-With");
    if (session == null) {
`if(httpRequest.getHeader("X-Requested-With")!=null && httpRequest.getHeader("X-Requested-With").equals("XMLHttpRequest")){`
        `logger.info("Ajax Expired...");`
                            `((HttpServletResponse)response).sendError(403);` // Response error set
                            `return;`
                        `}}`

3) In jsp whereever ajax code is written check request.readystate and request.state like this

if (req.readyState==4 && req.status==200)
         {
//your logic
}
else if(req.readyState==4 && req.status==403){

             alert("Your Session is Expired.Please Relogin.");
             window.location.href = "<%=request.getContextPath()%>/jsp/login.jsp";
         }