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。