Refresh the screen after a long calculation

Question

          Hi,
          I have a problem here:
          After I click a submit button, I want start a long process(running a stored procedure
          in
          database for about 20 mins) and after it is finished, screen will refresh automatically
          to reflect
          changes. I was using a thread to do the calculation but not able to refresh the
          browser after calculation is finished. Any one knows how to do it?
          Thanks.
          Kim
          

Answer 1

Kim,
          It was just pseudo-code to hand you an idea of using Refresh.
          As for the piece you provided, it has some problems:
          1. It looks like you start marginServer() Every time there is a refresh
          2. It looks like you have marginServer as a field in the servlet, which
          is not correct as it's not guaranteed that the same instance will serve
          the next request. You'd better keep in HttpSession.
          HTH.
          Regards,
          Slava Imeshev
          "Kim" <[email protected]> wrote in message news:[email protected]...
          >
          > Hi Slava,
          > Thanks for helping.
          > I tried your code but got some error . Here is the code:
          > public class LongRunningTaskRefresh extends HttpServlet {
          > public void doGet(HttpServletRequest request, HttpServletResponse response)throws
          > ServletException, IOException {
          > stillRunning =true;
          > marginServer.start(); //this is the thread with long
          > process. In the end of it, it will set stillRunning to false
          >
          > response.setContentType("text/plain");
          > PrintWriter out = response.getWriter();
          > if (stillRunning) {
          > response.setHeader("Refresh", "5");
          > out.println("Your request is being processed" );
          > }
          > else {
          > rd = request.getRequestDispatcher("MarginSummary.jsp");
          > rd.forward(request,response);
          > }
          > }
          > }
          >
          > Do I do anything wrong?
          >
          > THanks again!
          >
          > Kim
          >