在网上找了一个程序,觉得不错,拿来学习一下,可出现了的异常,请大侠帮忙改一下,不胜感激
jsp代码如下:
<%@ page contentType="text/html;charset=utf-8"%>
<%@ page import="java.util.*"%>
<%
if(request.getParameter("name")!=null)
{
session.setAttribute("uname",request.getParameter("name")) ;
}
%>
在线人员
<%
List l = (List)application.getAttribute("alluser") ;
Iterator iter = l.iterator() ;
while(iter.hasNext())
{
%>
<%
}
%>
异常如下:
org.apache.jasper.JasperException:An exception occured processing JSP page/online.jsp at line 37
<%
List l = (List)application.getAttribute("alluser") ;
Iterator iter = l.iterator() ;
while(iter.hasNext())
{
%>
Stacktrace:
.....
root cause
java.lang.NullPointerException
org.apache.jsp.onlin_jsp._jspService(online_jsp.java:99)
......