15-session 对象-设置，获取，清除session

package yucheng;

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;

@WebServlet("/se02")
public class HttpSession02 extends HttpServlet {
    @Override
    protected void service(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        System.out.println("获取Session对象 02");
        // 获取 session 对象 如何没有 session 对象 则新增一个
        HttpSession session = request.getSession();

        // 设置 session 对象
        session.setAttribute("name","yucheng");
        session.setAttribute("age","19");
        // 请求session 对象
        session.removeAttribute("age");

        // request 域对象
        request.setAttribute("bill","iiiii");
        // 请求转发
        // request.getRequestDispatcher("index.jsp").forward(request,response);
        // 重定向 可以拿到 session 对象 但是拿不到 request 对象
         response.sendRedirect("index.jsp");

    }
}