小编Bog*_*dan的帖子

我想检查一个Integer值是否为空。的值以Integer表格形式填写。这是我的代码。

这里引入了值：

<input name="varsta" placeHolder="Varsta:" type="text" data-constraints='@NotEmpty @Required @AlphaSpecial'> <br/><br/>

现在我想检查是否有数据引入。

protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

    response.setContentType("text/html;charset=UTF-8");
    PrintWriter out = response.getWriter();

    Integer varsta = Integer.parseInt(request.getParameter("varsta"));
    request.getSession().setAttribute("varsta", varsta);

    try {
        DBConnection connection = new DBConnection();
        Connection con = connection.Connect();

        PreparedStatement ps = con.prepareStatement(
            "insert into user(Nume,Prenume,E_mail,Parola,Varsta,Sex,Greutate,Inaltime,Nivel_activitate,Calcul_calorii)" + 
            "values ('"+nume+"','"+prenume+"','"+email1+"','"+parola+"','"+varsta+"','"+sex+"','"+greutate+"','"+inaltime+"','"+activitate+"','"+calorii+"')"
        );

        if (varsta == null && "".equals(varsta)) {
            String message = "Va rugam completati cu atentie TOATE campurile!";
            request.setAttribute("message", message);
            request.getRequestDispatcher("/inregistrare.jsp").forward(request, response);           
        } …