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

        PrintWriter pw = response.getWriter();
        pw.write(request.getRemoteAddr());
        pw.write(request.getRemotePort());
        pw.write(request.getLocalAddr());
        pw.write(request.getLocalPort());
    }

为什么只是端口号显示为问号，其他的显示正常。而改成println() 就正常了？？请高手看看。谢谢