<%@ page import="net.wen.bean.User" %>
<%@ page import="java.util.List" %>
<%@ page import="java.util.ArrayList" %><%--
Created by IntelliJ IDEA.
User: wen
Date: 2018/8/21
Time: 23:55
To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>Title</title>
</head>
<body>
<%
//request域中，存了一个小明
request.setAttribute("name","小明");
//session域中存了一个小红
User user = new User();
user.setName("小红");
user.setSex("女");
session.setAttribute("user",user);
//application域中存了一个list集合
List <User> list = new ArrayList<>();
User user1 = new User();
user1.setName("小绿");
user1.setSex("女");
User user2 = new User();
user2.setName("小黑");
user2.setSex("男");
list.add(user1);
list.add(user2);
application.setAttribute("list",list);
%>
<%--通过脚本获取request中name的值--%>
<%=request.getAttribute("name")%>
<%--通过脚本获取session中user中User对象的值--%>
<%
User user3 = (User) session.getAttribute("user");
String name = user3.getName();
String sex = user3.getSex();
out.write(name+","+sex);
%>
<%--通过脚本获取application中list的list对象中的值--%>
<%
List<User> list1 = (List<User>) application.getAttribute("list");
User user4 = list1.get(0);
out.write(user4.getName()+","+user4.getSex());
%>
<%--通过el表达式获取request、session、application中的多对应的值--%>
${requestScope.name}
${sessionScope.user.name}
${applicationScope.list[0].name}
<%--更简便的写法--%>
${name}
${user.name}
${list[0].name}
</body>
</html>
这就是el表达式在jsp中最常用的功能