As the title says: How do I show the .jsp extension in the URL when forwarding from Servlet to a JSP page without redirecting and thereby losing functionality of the Servlet?
If I forward from a Servlet to a JSP page by using the following code I still have the Servlet in my URL:
request.getRequestDispatcher("index.jsp").forward(request, response);
You don't.
The browser displays the URL that it thinks it's getting data from. Unless you tell it that it's getting a different URL via a redirect, it has no way to know what the server is doing behind the scenes. Nor should it.
From an application design perspective, you shouldn't care either. The only reason to use a unique URL is so that the user can set a bookmark. If the JSP page needs data from the servlet, then it doesn't make sense to give the user a different URL.
If you're dead set on giving the browser a ".jsp" URL, then have the servlet store data in the session. That's ugly, pointless, and subject to concurrent access issues, but it works.
You could redirect to the JSP instead of forwarding to it:
response.sendRedirect("index.jsp");
