Session timeout processing for Ajax in WEB development __javascript

In Java Web Development, when the session timeout, the normal page of the jump good processing. The request for Ajax timeout processing, you need special treatment.

First write a unified filter, or interceptor, for the AJAX request filtering process, the following example to filter for example:

    public void Dofilter (ServletRequest request, servletresponse response,
            Filterchain chain) throws IOException, servletexception {
        httpservletrequest servletrequest= (httpservletrequest) request;
        HttpServletResponse servletresponse= (httpservletresponse) response;
        Determine if it is an AJAX request, because AJAX requests append x-requested-with=xmlhttprequest
        if ("XMLHttpRequest". Equalsignorecase ( Servletrequest.getheader ("X-requested-with"))) {
            Servletresponse.addheader ("Sessionstatus", "timeout");
        }       
        Subsequent code omitted ...
    }

Then when invoking Ajax on the page, the capture results are timed out as follows:

Global AJAX access, processing Ajax sesion Timeout
$.ajaxsetup ({
    type:post,
    contentType: "Application/json;charset=utf-8 ",
    ///Use complete capture results, do timeout processing
    complete:function (XMLHttpRequest, textstatus) {
        var data = Xmlhttprequest.responsetext;
        if (data = = "Timeout") {
            if (window.top!= window.self) {
                window.top.location = "${ PageContext.request.contextPath} ";}}}
);

Based on the Header to determine whether it is an AJAX request, if it is Ajax to throw out a status code.

This section of the processing of the JS code, can be extracted as a method, so easy to use in other places directly.