web.xml中配置，session的计算是从停止操作session资源开始，包括获取，保存等

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10

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持久化：创建一个cookie覆盖之前服务器自动生成的JSESSIONID，设置持久化时间

GetSessionServlet.java

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package zyw.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;

@WebServlet(name = "GetSessionServlet",urlPatterns = "/getsession")

public class GetSessionServlet extends HttpServlet {

protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

}

protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

//获取session

HttpSession session = request.getSession();

String goods = (String)session.getAttribute("goods");//Ctrl + Alt + v

response.getWriter().write(goods+"");//加“”防止空指针

}

}

~~~

SaveSessionServlet.java

~~~

package zyw.session;

import javax.servlet.ServletException;

import javax.servlet.annotation.WebServlet;

import javax.servlet.http.*;

import java.io.IOException;

@WebServlet(name = "SaveSessionServlet",urlPatterns = "/savesession")

public class SaveSessionServlet 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();

//创建一个cookie覆盖之前服务器自动生成的JSESSIONID

Cookie cookie = new Cookie("JSESSIONID", session.getId());

cookie.setMaxAge(60*60);

response.addCookie(cookie);

session.setAttribute("goods","cup");

}

}

~~~