这个错在哪里了???

<%
String sql = "select * from vw_do_do where dbBillCode like 'RK%'";

Connection conn = null;
try{
conn = getConnection();
ResultSet rs = executeQuery(conn,sql);
List list=new ArrayList();
while(rs.next()){
RkVO iwarebill=new RkVO();
iwarebill.setDbBillCode(rs.getString("dbBillCode"));
iwarebill.setItemcode(rs.getString("itemcode"));
iwarebill.setItemname(rs.getString("itemname"));
iwarebill.setProdNumber(rs.getString("prodNumber"));
iwarebill.setInDate(rs.getString("inDate"));
iwarebill.setOutDate(rs.getString("outDate"));
list.add(iwarebill);
request.setAttribute("dd",list);
}
rs.close();
rs = null;
conn.close();
conn = null;
}catch(Exception ex){
out.println(ex.toString());
}

%>










<%
List aa=new ArrayList();
for(int i=0;i RkVO vo=new RkVO();
vo=(RkVO)aa.get(i);
%>








<%
}
%>

单据编码	产品编码	产品名称	产品数量	入库时间	出库时间
<%=vo.getDbBillCode()%>	<%=vo.getItemcode() %>	<%=vo.getItemname()%>	<%=vo.getProdNumber()%>	<%=vo.getInDate() %>	<%=vo.getOutDate() %>

我想点基每行记录的时候把这条记录对应的dbBillCode主键取出来(οnclick="javascript:getIndex(<%=vo.getDbBillCode()%>)" ),我这样做怎么老是出错呢,取不出来~~~!!!哎,我看着没错~~~~各位同事帮我看一下~~~~~thank you very much!!!!