Jsessionid.java

package cn.web.session;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.*;
import java.io.IOException;

// Session的实现是依赖于Cookie的

@WebServlet("/jsessionid")
public class Jsessionid extends HttpServlet {
    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        //1.获取session
        HttpSession session = req.getSession();
        System.out.println(session);

        //期望客户端关闭后，session也能相同
        // 创建Cookie,键为JSESSIONID，设置最大存活时间，让cookie持久化保存
        Cookie c = new Cookie("JSESSIONID", session.getId());
        c.setMaxAge(60 * 60);
        resp.addCookie(c);
    }

    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        this.doPost(req, resp);
    }
}