Como pegar o status do HttpServletResponse

public class AudFilter implements Filter {

     @Override
public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
		throws IOException, ServletException {

            final HttpServletRequest req = (HttpServletRequest) request;
	final HttpServletResponse resp = (HttpServletResponse) response;

              if (isAuthenticated(req)) {
		
		AudTrilha trilha = new AudTrilha();
                    trilha.setStatus("setar o status aqui");
             }

	chain.doFilter(req, resp);

}


       private boolean isAuthenticated(final ServletRequest request) {

	final HttpServletRequest req = (HttpServletRequest) request;
	if (req.getSession().getAttribute(USUARIO_KEY) == null)
		return false;
	return true;
}
}