JavaWeb(JSP中的JSTL核心标签学习) c:foreach报错500？ 错误原因：ArrayList＜String＞ people = new ArrayList＜＞()

1、错误原因

ArrayList people = new ArrayList<>()；

必须写成

ArrayList people = new ArrayList()；jdk7以下的版本，右边把String也加上 。

ArrayList people = new ArrayList<>();            这个是JDK7新特性。

2、错误代码

<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<%@ page import="java.util.ArrayList" %>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>


    



<%
    ArrayList people = new ArrayList<();
    //下标必须从0开始
    people.add(0,"张三");
    people.add(1,"李四");
    people.add(2,"王五");
    people.add(3,"赵六");
    people.add(4,"田七");
    request.setAttribute("list", people);
%>


<%--var: 每一次遍历出来的变量
    items: 要遍历的对象
    begin: 开始
    end: 结束
    step: 步长
--%>

     




    

3、正确代码

<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<%@ page import="java.util.ArrayList" %>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>


    



<%
    ArrayList people = new ArrayList();
    //下标必须从0开始
    people.add(0,"张三");
    people.add(1,"李四");
    people.add(2,"王五");
    people.add(3,"赵六");
    people.add(4,"田七");
    request.setAttribute("list", people);
%>


<%--var: 每一次遍历出来的变量
    items: 要遍历的对象
    begin: 开始
    end: 结束
    step: 步长
--%>