登陆用户名和密码判断+验证码验证
省略dao层和service层
1、生成验证码的number.jsp
<%@ page contentType="image/jpeg" language="java" import="java.util.*,java.awt.*,java.awt.image.*,javax.imageio.*" pageEncoding="utf-8"%> <%! Color getRandColor(int fc,int bc){ Random random = new Random(); if(fc > 255){ fc = 255; } if(bc < 255){ bc = 255; } int r = fc +random.nextInt(bc-fc); int g = fc +random.nextInt(bc-fc); int b = fc +random.nextInt(bc-fc); return new Color(r,g,b); } %> <% //设置页面不缓存 response.setHeader("Pragma","no-cache"); response.setHeader("Cache-Control","no-catch"); response.setDateHeader("Expires",0); //在内存中创建图象 int width = 60; int height = 20; BufferedImage image = new BufferedImage(width,height,BufferedImage.TYPE_INT_RGB); //创建图象 Graphics g = image.getGraphics(); //生成随机对象 Random random = new Random(); //设置背景色 g.setColor(getRandColor(200,250)); g.fillRect(0,0,width,height); //设置字体 g.setFont(new Font("Tines Nev Roman",Font.PLAIN,18)); //随机产生干扰线 g.setColor(getRandColor(160,200)); for(int i = 0; i < 255; i++){ int x = random.nextInt(width); int y = random.nextInt(height); int xl = random.nextInt(12); int yl = random.nextInt(12); } //随机产生认证码,4位数字 String sRand = ""; for(int i = 0; i < 4; i++){ String rand = String.valueOf(random.nextInt(10)); sRand += rand; //将认证码显示到图象中 g.setColor(new Color(20 + random.nextInt(110),20 + random.nextInt(110),20 + random.nextInt(110))); g.drawString(rand,13*i+6,16); } session.setAttribute("rCode",sRand); //图像生效 g.dispose(); //输出图像到页面 ImageIO.write(image,"JPEG",response.getOutputStream()); out.clear(); out = pageContext.pushBody(); %>
session.setAttribute("rCode",sRand); 这是把生成的验证码放入Session中。便于验证时候获取
2、checkLoginServlet.java
public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { response.setContentType("text/html"); PrintWriter out = response.getWriter(); String username = request.getParameter("username"); String password = request.getParameter("password"); String code =request.getParameter("ucode"); UserService userService=new UserServiceImpl(); String rCode =(String) request.getSession().getAttribute("rCode"); System.out.println("username=============="+username); //用户名是否存在 if(!userService.checkUsername(username)){ out.write("unregistered"); }else if(!code.equals(rCode)){ out.write("codeerror"); }else if(!userService.checkIsAdmin(username)){ out.write("noadmin"); }else { //用户名是否被锁 if(!userService.checkUsernameStatus(username)){ out.write("forzen"); } //用户名和密码是否正确 if(!userService.checkLogin(username, password)){ out.write("fail"); }else{ out.write("success"); } } //判断用户名是否存在，不存在，存在后再判断p }
3、jsp页面 login.jsp
<%@ 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" /> <meta http-equiv="X-UA-Compatible" content="IE=edge"> <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no" /> <meta name="renderer" content="webkit"> <title>登录</title> <link rel="stylesheet" href="../css/pintuer.css"> <link rel="stylesheet" href="../css/admin.css"> <script src="../js/jquery.js"></script> <script src="../js/pintuer.js"></script> <script type="text/javascript"> $(document).ready(function(){ $("#btnLogin").click(function(){ var username = $("#username").val(); var password = $("#password").val(); var ucode = $("#code").val(); if(username =="" || password==""){ alert("用户名和密码不能为空"); }else{ $.ajax({ type:"POST", url:"<%=request.getContextPath()%>/CheckLoginServlet", data:{ "username":username, "password":password, "ucode":ucode }, contentType:"application/x-www-form-urlencoded", success:function(msg){ if(msg=="unregistered"){ alert("对不起，该用户未注册"); } if(msg=="forzen"){ alert("对不起，该用户已被锁"); } if(msg="noadmin"){ alert("对不起，你没有管理员权限"); } if(msg=="fail"){ alert("对不起，密码错误"); } if(msg =="codeerror"){ alert("验证码错误"); } if(msg=="success"){ parent.document.location.href="<%=request.getContextPath()%>/admin/index.jsp"; } }, }); } return false; }); }); </script> </head> <body> <div class="bg"></div> <div class="container"> <div class="line bouncein"> <div class="xs6 xm4 xs3-move xm4-move"> <div style="height:150px;"></div> <div class="media media-y margin-big-bottom"> </div> <form id="form1"> <div class="panel loginbox"> <div class="text-center margin-big padding-big-top"><h1>后台管理中心</h1></div> <div class="panel-body" style="padding:30px; padding-bottom:10px; padding-top:10px;"> <div class="form-group"> <div class="field field-icon-right"> <input id="username" type="text" class="input input-big" name="name" placeholder="登录账号" data-validate="required:请填写账号" /> <span class="icon icon-user margin-small"></span> </div> </div> <div class="form-group"> <div class="field field-icon-right"> <input type="password" id="password" class="input input-big" name="password" placeholder="登录密码" data-validate="required:请填写密码" /> <span class="icon icon-key margin-small"></span> </div> </div> <div class="form-group"> <div class="field"> <input type="text" class="input input-big" id="code" name="code" placeholder="填写右侧的验证码" data-validate="required:请填写右侧的验证码" /> <img src="number.jsp" id="safeCode"/><a id="changeCode" href="#">看不清，换一张</a> </div> </div> </div> <div style="padding:30px;"><input type="submit" id="btnLogin" class="button button-block bg-main text-big input-big" value="登录"></div> </div> </form> </div> </div> </div> </body> </html>
比较简单的4位数字图片验证码。