Question

I am trying to implement a filter for all my files excluding login.jsp. I understand that filter mapping cannot exclude certain files. What I need to do is to create another filter to map just the login.jsp. How do I create another file that with url pattern /login.jsp and without SessionFilter being processed after it?
Here is part of my code for session filter for all files.

public class SessionFilter implements Filter{ 
   RequestDispatcher rd = null; 

  public void doFilter(ServletRequest request, ServletResponse response, FilterChain filterChain) 
   throws IOException, ServletException{ 
      HttpServletRequest request = (HttpServletRequest)request; 
      HttpSession session = request.getSession(); 

   // New Session so forward to login.jsp 
   if (session.isNew()){ 
     rd = request.getRequestDispatcher("login.jsp"); 
     rd.forward(request, response); 
  } 

  // Not a new session so continue to the requested resource 
   else{ 
      filterChain.doFilter(request, response); 
  } 
} 

Answer 1

You can check if the requested path is in your “excluded list” with request.getServletPath().

If you want a new Filter separated from SessionFilter, you could either set a special flag as request attribute (such as “loginPage”) which will be checked by other filters (if you want a new Filter separated from SessionFilter) or you can simply not invoke the chain.doFilter().

If you’re modifying SessionFilter, just don’t redispatch to “login.jsp”