多级下拉菜单的级连显示问题

                                  i=i+1;

                           }

                    }

                 String last_xml = xml_start + xml + xml_end;

                 //System.out.println("last_xml:"+last_xml);

                //  last_xml = new String(last_xml.getBytes("UTF-8"), "GB2312");

                response.getWriter().write(last_xml);

             }// try

             catch  (Exception e){

                    System.out.print(e.getMessage());

             }      

       }

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

              doGet(request,response);

      }

       public void init() throws ServletException {

       }

}