使用HashMap没有获取到值

来源：2-9 自由编程

慕容6190480

2019-08-09 13:25:01

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
</head>
<body>
    ${requestScope.d }
    <c:choose>
        <c:when test="${d=='Monday'}">
            <h2 style="color:bulue"> 星期一</h2>
        </c:when>
        <c:otherwise>
            <h2 style="color:red">内容不对！</h2>
        </c:otherwise>
    </c:choose>
</body>
</html>

package com.imooc.jstl;

import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * Servlet implementation class JstlServlet
 */
@WebServlet("/Jstl")
public class JstlServlet extends HttpServlet {
    private static final long serialVersionUID = 1L;
       
    /**
     * @see HttpServlet#HttpServlet()
     */
    public JstlServlet() {
        super();
        // TODO Auto-generated constructor stub
    }

    /**
     * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doGet(HttpServletRequest request, HttpServletResponse response) 
            throws ServletException, IOException {
        request.setAttribute("score", 58);
        request.setAttribute("grade", "D");
        request.setAttribute("X", 5);
        Map<String,String> day=new HashMap<String,String>();
        day.put("Monday","星期一");
        day.put("Tuesday", "星期二");
        day.put("Wednesday", "星期三");
        day.put("Thursday", "星期四");
        day.put("Friday", "星期五");
        day.put("Saturday", "星期六");
        day.put("Sun", "星期日");
        Set<String> d=day.keySet();
        request.setAttribute("day",d);
        request.getRequestDispatcher("/day.jsp").forward(request, response);
        
    }

}

http://localhost:8080/jstl/day.jsp
页面显示这条信息，这个是要循环遍历才能实现吧？不知道该怎么操作了。

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