一、添加商品
package com.session;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.*;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
@WebServlet(name = "AddServlet",urlPatterns = "/addcart")
public class AddServlet extends HttpServlet {
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
String name = request.getParameter("name");
HttpSession session = request.getSession();
List list = (List)session.getAttribute("list");
if(list==null){
//第一次訪問時，session中沒有attribute屬性
list = new ArrayList();
}
list.add(name);
session.setAttribute("list",list);
Cookie cookie = new Cookie("JSESSIONID", session.getId());
cookie.setMaxAge(3600);
cookie.setPath("/");
response.addCookie(cookie);
}
}
二、添加商品html
<body>
<h1>商品列表</h1>
<a href="/addcart?name=杯子">杯子</a>
<a href="/addcart?name=書包">書包</a>
<a href="/addcart?name=筆記本">筆記本</a>
</body>
三、獲取商品
package com.session;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.io.IOException;
import java.util.List;
@WebServlet(name = "GetCartServlet",urlPatterns = "/recart")
public class GetCartServlet extends HttpServlet {
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
HttpSession session = request.getSession();
List<String> list = (List)session.getAttribute("list");
response.setContentType("text/html;charset=utf-8");
for(String s : list){
response.getWriter().write(s);
}
}
}