JSP内置对象---request和 response
<%@page import="java.net.URLEncoder"%> <%@page import="com.hanqi.web.CardDAO"%> <%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title>Insert title here</title> </head> <body> <% //设置不缓存页面 response.setHeader("Cache_Control", "no-cache"); //定时跳转 //response.setHeader("refresh", "2;URL=http://www.baidu.com"); //接受数据 String cairnumber =request.getParameter("cairnumber"); String password =request.getParameter("password"); if(cairnumber==null || password == null||cairnumber.equals("")||password.equals("")) { out.write("请正确登录系统"); } else { //检查登入信息 CardDAO cd=new CardDAO(); if(cd.checkLogin(cairnumber, password)) { //out.write("登入成功"); //无缓存的直接发送 response.getWriter().write("验证成功"); //创建cookie Cookie ck= new Cookie("cairnumber",cairnumber); ck.setMaxAge(10*24*60*60);//设置过期时间 //发送 response.addCookie(ck); //对中文进行转码 Cookie ck1 =new Cookie("username",URLEncoder.encode("张三")); response.addCookie(ck1); //创建session session.setAttribute("cairnumber", cairnumber); session.setAttribute("username", "李四"); //设置session超时的时间 //默认设置是20分钟 //如果连续超过20分钟没有任何请求发送给服务器,session就失效 //session.setMaxInactiveInterval(30); //页面跳转 response.sendRedirect("Main.jsp"); //response.sendRedirect("http://www.baidu.com"); } else { out.write("登入失败"); //跳回登入页面 response.setHeader("refresh", "2;URL=Login.jsp"); } } %> </body> </html>
<%@page import="java.net.URLDecoder"%> <%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title>Insert title here</title> </head> <body> 系统主页面 <br> cookie列表 <br> <% //检查cookie //获得cookie集合 Cookie[] cks= request.getCookies(); for(Cookie ck: cks) { //解码 out.write(ck.getName()+"="+URLDecoder.decode(ck.getValue()) +"<br>"); } %> <br> <br> <% //判断session String cairnumber = session.getAttribute("cairnumber").toString(); out.print("cairnumber="+cairnumber); %> <br> <a href="TestLogin.jsp">测试是否已登录的页面</a> </body> </html>
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title>Insert title here</title> </head> <body> <% Object obj =session.getAttribute("cairnumber");//判断session是否存在 if(obj==null) { out.print("您没有登入") ; response.setHeader("refresh", "2;URL=Login.jsp"); } else { out.print("cairnumber="+obj.toString()); //销毁所有session //session.invalidate(); //移除某个属性 session.removeAttribute("cairnumber"); } %> </body> </html>