jsp使用session、Cookie登录状态验证

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>









	
		账户名:
	
	
		密码:
	
	登录

servlet自己需要配置web.xml哦 

package com.jmh.servlet;

import java.io.IOException;
import java.io.PrintWriter;
import java.sql.SQLException;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import com.jmh.dao.Tb_LogonDao;
import com.jmh.entity.Tb_Logon;


public class LogonServlet extends HttpServlet{
	@Override
	protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
	this.doGet(req, resp);
	}
	@Override
	protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
	//设置编码
		req.setCharacterEncoding("utf-8");
		resp.setContentType("text/html;charset=utf-8");
	//获取out、session对象
		PrintWriter out = resp.getWriter();
		HttpSession session = req.getSession();
	//处理业务逻辑代码
		//获取传入过来的值
		String oname = req.getParameter("oname");
		String opwd = req.getParameter("opwd");
		//实例化实体类
		Tb_Logon lo=new Tb_Logon(oname, opwd);
		//实例化方法类
		Tb_LogonDao tbl=new Tb_LogonDao();
		try {
			boolean logon = tbl.Logon(lo);
			if(logon) {//登录成功
				//登录状态:登录成功后把用户名传入给session作用域
				session.setAttribute("oname", oname);
				req.getRequestDispatcher("登录成功后要跳转的页面").forward(req, resp);
			}else {//登录失败
				out.print("");
			}
		} catch (SQLException e) {
			e.printStackTrace();
		}
	}

}

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>








	<%
	String str=(String)session.getAttribute("oname");
	if(null==str){//没有登录
		out.print("");
	}
	%>

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>








<%@ include file="sessionLogon.jsp" %>

登录成功!

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>









	
		账户名:
	
	
		密码:
	
	登录

 servlet自己需要配置web.xml哦 

package com.jmh.servlet;

import java.io.IOException;
import java.io.PrintWriter;
import java.sql.SQLException;

import javax.servlet.ServletException;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import com.jmh.dao.Tb_LogonDao;
import com.jmh.entity.Tb_Logon;


public class LogonServlet extends HttpServlet{
	@Override
	protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
	this.doGet(req, resp);
	}
	@Override
	protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
	//设置编码
		req.setCharacterEncoding("utf-8");
		resp.setContentType("text/html;charset=utf-8");
	//获取out、session对象
		PrintWriter out = resp.getWriter();
		HttpSession session = req.getSession();
	//处理业务逻辑代码
		//获取传入过来的值
		String oname = req.getParameter("oname");
		String opwd = req.getParameter("opwd");
		//实例化实体类
		Tb_Logon lo=new Tb_Logon(oname, opwd);
		//实例化方法类
		Tb_LogonDao tbl=new Tb_LogonDao();
		try {
			boolean logon = tbl.Logon(lo);
			if(logon) {//登录成功
				//使用Cookie
				Cookie ck=new Cookie("oname", oname);
				resp.addCookie(ck);//将Cookie对象输出客户端
				resp.sendRedirect("登录成功后跳转指定的页面");
			}else {//登录失败
				out.print("");
			}
		} catch (SQLException e) {
			e.printStackTrace();
		}
	}

}

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>








<%	
	boolean f=false;
	//获取所有Cookie
	Cookie[] ck= request.getCookies();
	//遍历Cookie
	for(Cookie c : ck){
		//非空判断
		if(null!=c){
			if(c.getName().equals("oname")){
				f=true;//已经登录
				break;
			}
		}
	}
	if(f==false){
		out.print("");
	}
%>

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>








<%@ include file="cookieLogon.jsp" %> 

登录成功!