报错部分：严重: Servlet.service() for servlet jsp threw exception
java.lang.NullPointerException
at com.risinginfo.nta.common.codelist.CodeListObjImpl.getList(CodeListObjImpl.java:39)
at com.risinginfo.nta.common.tag.SelectBoxTag.doEndTag(SelectBoxTag.java:71)
at org.apache.jsp.jsp.usermanage.user.addUser_jsp._jspx_meth_nta_005fcodelist_005f0(addUser_jsp.java:1183)
at org.apache.jsp.jsp.usermanage.user.addUser_jsp._jspx_meth_html_005fform_005f0(addUser_jsp.java:644)
at org.apache.jsp.jsp.usermanage.user.addUser_jsp._jspService(addUser_jsp.java:253)
空指针异常，但是我到addUser.jsp里没有发现哪个参数是空的，这是action里对增加的处理： UserForm userform = (UserForm)form;
User user = new User();
BeanUtils.copyProperties(user, userform);
IUserManageService userService = (IUserManageService)getService("serviceUserManage",request);
IGetTreeNumService treeService = (IGetTreeNumService) getService("serviceTreeKpi", request);
int[] treeNum = treeService.getTreeNum(request,"userManage.do?method=jumpPage");
if(treeNum[0] == 0)
treeNum[0] = treeNum[1];
request.setAttribute("parN", treeNum[0]);
request.setAttribute("nowN", treeNum[1]);
