import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
public class login extends HttpServlet
{
    public void doPost(HttpServletRequest req,HttpServletResponse resp)throws ServletException,IOException
    {
        String user=req.getParameter("user");
        String password=req.getParameter("password");
        String sTxt="您输入的是:"+user+password;
        resp.setContentType("text/html;charset=gb2312");
        PrintWriter out=resp.getWriter();
        out.println(sTxt);
        out.close();
    }
}
用户名user里输入中文后,打印出来就是问号:您输入的是:????123456。通过html post进来的。