•设计程序，用户选择选择喜好的背景颜色（红/黄/绿），提交后创建Cookie并存储用户名及颜色信息，cookie有效期设置为300秒，然后在当前servlet中跳转到test.jsp页面

本文链接：https://blog.youkuaiyun.com/lengleng0107/article/details/121202100

本文介绍如何设计一个程序，用户通过选择背景颜色（红、黄、绿），设置Cookie存储用户信息，然后跳转到test.jsp页面展示用户名并改变背景色。同时强调了处理中文字符和Cookie的有效期管理。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

设计程序，用户选择选择喜好的背景颜色（红/黄/绿），提交后创建Cookie并存储用户名及颜色信息，cookie有效期设置为300秒，然后在当前servlet中跳转到test.jsp页面，在test.jsp页面显示用户名，及改变页面的背景颜色。注意不要使用Eclipse内置浏览器，随后关闭浏览器，再重新打印浏览器，直接访问text.jsp

在输入用户登录时候请不要输入汉字，否则报Cookie值或属性中的控制字符异常

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<body>
<form action="servlet" method="post">
用户名:<input type="text" id="name" name="name"><br>
挑选颜色：<input type="radio" id="color1" name="color" value="red">红
          <input type="radio" id="color2" name="color" value="yellow">黄
          <input type="radio" id="color3" name="color" value="green">绿
<input type="submit" value="提交">
</form>
</body>
</html>

package servlet;

import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
* Servlet implementation class Servlet
*/
@WebServlet("/servlet")
public class Servlet extends HttpServlet {
private static final long serialVersionUID = 1L;

/**
* @see HttpServlet#HttpServlet()
*/
public Servlet() {
super();
// TODO Auto-generated constructor stub
}

   /**
   * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
   */
   protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
       // TODO Auto-generated method stub
       response.getWriter().append("Served at: ").append(request.getContextPath());
   }

   /**
   * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
   */
   protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
       request.setCharacterEncoding("utf-8");
       response.setContentType("text/html;charset=utf-8");
       String name = request.getParameter("name");
       String color = request.getParameter("color");
       Cookie c1 = new Cookie("name", name);
       Cookie c2 = new Cookie("color", color);
       c1.setMaxAge(60*5);
       c2.setMaxAge(60*5);
       response.addCookie(c1);
       response.addCookie(c2);
       request.getSession().setAttribute("name", name);
       request.getSession().setAttribute("color", color);
       response.sendRedirect("test.jsp");
   }

}

<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8" %>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<%
String name = null;

Cookie [] cookie = request.getCookies();
for(int i=0;i<cookie.length;i++){
   name=cookie[i].getValue();
   if(i==0){
       break;
   }
}
String color = null;
for(int i=1;i<cookie.length;i++){
   color=cookie[i].getValue();
   if(i==0){
       break;
   }
}
%>
<body bgcolor="<%=color %>">
欢迎您：<%=name %>
<%=color %>
</body>
</html>