how do we use request.session.setAttribute for already existing session variable to UI

Question

While loading the view page I am setting a session variable as:

request.session.setAttribute("list",list);

after that onclick of a button I am using ajax call to refresh the list. in backend I am able to see the latest list contents. But in UI I am using :

List<String> cList = (List<String>)session.getAttribute("list");

but even after the list is changed I am not able see the latest list contents.Still the old list contents are displaying on the page. Need some suggestions on how to resolve this issue.

var refreshThisDiv= "refreshThisDiv";
            var goUrl= "unametest/getUserNamesList;
            var httpRequest=null;
            var refreshContent = "null";
            httpRequest = XMLHTTPObject();
            httpRequest.open("POST", goUrl, true);
            httpRequest.onreadystatechange = function () {ajaxFcuntion(refreshThisDiv,httpRequest); } ;
            httpRequest.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
            httpRequest.send(null);

//ajaxFcuntion
function ajaxFucntion(refreshThisDiv,httpRequest){

    if (httpRequest.readyState == 4)
    {
        if(httpRequest.status == 200)
        {
            results =  httpRequest.responseText; 
if(results!=null){

            <%

            List<String> list = (List<String>)request.getSession().getAttribute("list"); %>
//display data from list
}

}

Show more code, especially from the UI (the AJAX call, how the AJAX response is processed). These two lines are not enough to understand what's happening. — Jozef Chocholacek, Aug 24 '16 at 06:59
@JozefChocholacek hi Thanks for the reply. I have added the code. Please have a look. — user3213490, Aug 24 '16 at 07:21

score 1 · Answer 1 · edited May 23 '17 at 10:28

1

Actually as expected, you are mixing two different codes. You have to realize, where and when each code is executed - JSP on the server when the page is requested and rendered (i.e. before the response is send to the browser) and Javascript in the browser, after the browser receives the already generated response. For more details how to use AJAX, JSP and servlets together, read this question and answer carefuly.

edited May 23 '17 at 10:28

Community

1
1

answered Aug 24 '16 at 07:39

Jozef Chocholacek

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okay so how should I change the implementation to make it work . I have no idea and I am struck here. need some alternatives please. @Jozef Chocholacek – user3213490 Aug 24 '16 at 07:42
Read the linked answer, there is a lot of examples, one exactly doing what you need. – Jozef Chocholacek Aug 24 '16 at 07:45

how do we use request.session.setAttribute for already existing session variable to UI

1 Answers1