Session variables in ServletRequest

Question

I need to access session variables through a filter. I don't even know if it is possible. In practice, the problem is that the doFilter method type from javax.Servlet.Filter implementation is ServletRequest, whilst HttpServlet inherited classes, doPost method parameter request is HttpServletRequest.

1. Can I access session in ServletRequest in a Filter?
2. Should I do that?
3. What could you recommend me?

Thanks!

Answer 1

Just cast the obtained ServletRequest to HttpServletRequest.

@Override
public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws IOException, ServletException {
    HttpServletRequest request = (HttpServletRequest) req;
    HttpSession session = request.getSession(false);
    // ...
}

See also:

• Our servlet-filters wiki page