我从数据库取几条记录然后保存到List对象中 然后再保存到 session里面
但是在jsp页面操作的时候对List操作的时候怎么总是有错误显示?比如:right.jsp
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@ page import="java.util.List" %>
<%@ page import="DAO.Right" %><%
List rightList=(List)session.getAttribute("list");
int i=rightList.size();
%>
总是说有颜色的地方有错误.是为什么??
但是在jsp页面操作的时候对List操作的时候怎么总是有错误显示?比如:right.jsp
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@ page import="java.util.List" %>
<%@ page import="DAO.Right" %><%
List rightList=(List)session.getAttribute("list");
int i=rightList.size();
%>
总是说有颜色的地方有错误.是为什么??
List rightList=(List)session.getAttribute("list");
int i=rightList==null?0:rightList.size();
%>
<%@ page import="java.util.List" %>
<%@ page import="DAO.Right" %><%
List rightList=(List)session.getAttribute("list");
int i=0;
if(rightList!=null)i=rightList.size();
%>
这样靠猜没办法解决的
1。注意session 与request的用法
2。或许你本身在后台class里面就出现了问题
Java/J2EE技术教程
List rightList=(List)session.getAttribute("list");
int i=rightList==null?0:rightList.size();
%>
<logic:iterate id="alarmDTO" name="warnList">
<tr>
<td height="27" align="left" class="td3Dotted textblack"> </td>
<td class="td3Dotted textblack"><bean:write name="alarmDTO" property="custName"/> </td>
<td class="td3Dotted textblack"><bean:write name="alarmDTO" property="alarmName"/> </td>
<td class="td3Dotted textblack"><bean:write name="alarmDTO" property="className"/> </td>
<td class="td3Dotted textblack"><bean:write name="alarmDTO" property="startTime"/> </td>
<td class="td3Dotted textblack"><bean:write name="alarmDTO" property="finishTime"/> </td>
<td align="center" class="td3Dotted textblack"><strong>[<SPAN style="cursor:hand" onclick="fun2('<bean:write name="alarmDTO" property="id"/>');">查看</SPAN>]</strong></td>
</tr>
</logic:iterate>
</logic:present>