Ndtyjky

The code below works to increase the counter for every page a visitor goes too however i'm needing to work out how to make it so it doesn't allow an increase in counts on the same page over one (to stop someone spamming refresh and increasing the view count). Is there a way to check if the URL has changed within a java servlet?

CODE

HttpSession session = request.getSession() ;    // Will create new 

    session.setAttribute("timesLoggedIn", 0);

    session.setAttribute("pictureNames", null);

     // session.setAttribute("pictureNames", null);

    Integer accessCount = (Integer)session.getAttribute("timesLoggedIn") ;

    String pictureNames = request.getPathInfo();

    String pathName = (String)session.getAttribute("pictureNames");

    String id = session.getId();



    //start session

    //increment count by one

    //if count already implemented, don't implement.



    out.println(pathName);

      if (accessCount < 1 && pathName == null) {



           out.println("<h1>This is your first visit!</h1>");

           session.setAttribute("timesLoggedIn", 1);

           session.setAttribute("pictureNames", pictureNames);

             Utilities.IncreaseCount(out, pictureName);





        }



      out.println(pathName);

You can get the current page path with the servlet request API, such as request.getPathInfo()

You could then use this to create a session attribute key unique to the page. If there would be characters in the page path that are not permitted to be part of a session attribute key then you could obviously replace the characters in the string. It would be up to you to determine whether you would want to also consider query parameters as unique pages, e.g. /page1?a=1 vs /page1?a=2

Then it would be trivial in your if/else to say if the key does not exist, put the value there with 1. If the key is already in the session, do not increment it, just read the value to display it.

Be mindful that if you do consider query params unique pages and this would have different keys for /page1?a=1 vs /page1?a=2 it could be potentially dangerous for memory consumption as a nasty use who figures this out could in theory write a script to request many different pages using unique query params which would slowly but surely fill the session with lots of small bit of data but could eventually over a sustained period of time be some sort of denial of service via polluting your session storage.