Large amount of data submitted by form post

problem ： page 1 After submission , If the amount of data is too large , page 2 Can't get , The value obtained is null
resolvent ：
POST No problem with delivery .
stay tomcat It set up server.xml

<Connector port="80" protocol="HTTP/1.1" 
  connectionTimeout="20000" 
  redirectPort="8443"
  maxPostSize="2000000"/>
  //maxPostSize  This attribute 0 Represent unlimited  

jsp page 1

<form name = "transferform" method = "post" action = "excel_create.jsp">
  <input name="tabletitle" type="hidden" value="">
  <input name="tablevalue"  value="">
  <script language="JavaScript">
  var oldborder;
   if(parent.Gridtable){
     oldborder=parent.Gridtable.border;
     parent.Gridtable.border="1";
   }
   transferform.tabletitle.value = parent.TABLE_TITLE.innerText;
   transferform.tablevalue.value = parent.TABLE_DATA.innerHTML;

    transferform.submit();
    if(parent.Gridtable){
      parent.Gridtable.border=oldborder;
    }
    </script>
</form>

jsp page 2

response.setCharacterEncoding("utf-8");
String data=(String)request.getParameter("tablevalue");
String title=(String)request.getParameter("tabletitle");
String filename=title+".cls";
response.setHeader("Content-Disposition","attachment;filename=" + new String("default_excel.xls".getBytes("GBK"), "ISO-8859-1"));