会话技术Session快速入门、原理分析

会话技术-Session-快速入门

　　1.概念：服务器端会话技术，在一次会话的多次请求间共享数据，将数据保存在服务器端的对象中。HttpSession

　　2.快速入门：

　　　　1.获取HttpSession对象：

　　　　　　HttpSession session = request.getSession();

　　　　2.使用HttpSession对象：

　　　　　　Object getAttribute(String name)

　　　　　　void setAttribute(String name,Object value)

　　　　　　void removeAttribute(String name)

package com.example.session;

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

@WebServlet("/SessionDemo1")
public class SessionDemo1 extends HttpServlet {
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // 使用session共享数据

        // 1.获取session
        HttpSession session = request.getSession();
        // 2.存储数据
        session.setAttribute("msg","hello session");
    }

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

package com.example.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("/SessionDemo2")
public class SessionDemo2 extends HttpServlet {
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // 使用session获取数据

        // 1.获取session
        HttpSession session = request.getSession();
        // 2.获取数据
        Object msg = session.getAttribute("msg");
        System.out.println(msg);
    }

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

会话技术-Session-原理分析

　　Session的实现是依赖于Cookie的。