Difference between revisions of "Cookies and session tracking"

Revision as of 09:14, 24 May 2014

RequestDispatcher dispatcher = getServletContext().getRequestDispatcher("/urlToServlet");
dispatcher.forward(request, response);

And this is how to deal with cookies.

create and send cookies

Cookie userCookie = new Cookie("name", "value");
userCookie.setMaxAge(60*60*24*365); //Store cookie for 1 year
response.addCookie(userCookie);

read cookie from client

 cookieName = "somecookie";
Cookie[] cookies = request.getCookies();

if (cookies != null) {

   for(int i=0; i<cookies.length; i++) 
   {
       Cookie cookie = cookies[i];
       if (cookieName.equals(cookie.getName())) 
       {
           doSomethingWith(cookie.getValue());
       }
   }

} else {

   //do something else for firsttime visitors 

}

Are you using cookies for session tracking? If yes, then use HttpSession. Using HttpSession then there is not need to directly involve with cookies for session tracking.

For example, in a simple login page, this is what you do

HttpSession session = request.getSession();
session.setAttribute("username",username);
In other pages,
if(session.getAttribute("username")==null)
{
//forward to login page.
}