Fliter登入控制

public void doFilter(ServletRequest req, ServletResponse resp, FilterChain chain) throws ServletException, IOException {
    HttpServletRequest request = (HttpServletRequest) req;
    HttpServletResponse response = (HttpServletResponse) resp;
    String url = request.getRequestURI();

    String username = "";
    String password = "";
    Cookie[] sc = request.getCookies();
    if(null!=sc){
        for(Cookie c: sc){
            if("username".equals(c.getName())){
                username= c.getValue();
            }
            if("userpass".equals(c.getName())){
                password = c.getValue();
            }
        }
    }

    //忽略index.jsp .css .js .jpg等
    if(url.endsWith(".css")||url.endsWith(".js")||url.endsWith(".jpg") ||url.endsWith(".gif")
            ||url.endsWith(".png")||url.endsWith("/index.jsp")||url.endsWith("/LoginServlet")){
        chain.doFilter(request, response);
    }else {
        User user = new User(username,password);
        UserDaoImpl ud = new UserDaoImpl();
        if (ud.isUser(user)){
            chain.doFilter(request, response);
        }else {
            response.sendRedirect("index.jsp");
        }
    }
}