@Overrideprotected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
    resp.setContentType("text/html");
    PrintWriter pw = resp.getWriter();

    String name = req.getParameter("name");
    String word = "world";
    if (name != null && !name.isBlank()) {
        word = name;
    }
    pw.write("<h1>Hello, " + word + "!");
    pw.flush();
}