Question

I am able to set session attribute in scriptlet but when I am trying to set session attribute inside java class it shows error like “session cannot be resolved”.
So how to set session in java?

<%String username = (String)request.getAttribute("un");
session.setAttribute("UserName", username);%>

Answer 1

By Java class, I am assuming you mean a Servlet class as setting session attribute in arbitrary Java class does not make sense.You can do something like this in your servlet’s doGet/doPost methods

public void doGet(HttpServletRequest request, HttpServletResponse response) {

    HttpSession session = request.getSession();
    String username = (String)request.getAttribute("un");
    session.setAttribute("UserName", username);
}