jquery验证码的例子--six

今天研究了jquery验证码的例子，和大家分享一下，也记录自己的点滴进步~~呵呵~~

1、VerifyCodeServlet.java

package verify;

import java.awt.Color;     
import java.awt.Font;     
import java.awt.Graphics2D;     
import java.awt.image.BufferedImage;     
import java.util.Random;     
    
import javax.imageio.ImageIO;     
import javax.servlet.ServletException;     
import javax.servlet.ServletOutputStream;     
import javax.servlet.http.HttpServlet;     
import javax.servlet.http.HttpServletRequest;     
import javax.servlet.http.HttpServletResponse;     
import javax.servlet.http.HttpSession;     
     
public class VerifyCodeServlet extends HttpServlet {     
   
private static final long serialVersionUID = 1L;

// 验证码图片的宽度。     
     private int width = 140;     
     
    // 验证码图片的高度。     
     private int height = 60;     

     // 验证码字符个数     
    private int codeCount = 4;     
    
     private int x = 0;     

     // 字体高度     
     private int fontHeight;     
    
     private int codeY;     
     //去掉o和0，i和1
    char[] codeSequence = { 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'J',     
            'K', 'L', 'M', 'N', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W',     
             'X', 'Y', 'Z', '2', '3', '4', '5', '6', '7', '8', '9' };     
     
     /**   
      * 初始化验证图片属性  ，从web.xml中获得 
      */    
     public void init() throws ServletException { 
        // 宽度     
         String sWidth = this.getInitParameter("width");     
        // 高度     
        String sHeight = this.getInitParameter("height");     
         // 字符个数     
        String sCodeCount = this.getInitParameter("codeCount");     
    
         //将配置的信息转换成数值     
        try {     
             if (sWidth != null && sWidth.length() != 0) {     
                 width = Integer.parseInt(sWidth);     
            }     
           if (sHeight != null && sHeight.length() != 0) {     
                 height = Integer.parseInt(sHeight);     
             }     
             if (sCodeCount != null && sCodeCount.length() != 0) {     
                 codeCount = Integer.parseInt(sCodeCount);     
             }     
         } catch (NumberFormatException e) {     
        }     
     
        x = width / (codeCount + 1);     
         fontHeight = height - 2;     
         codeY = height - 4;     
     
     }     
     
     protected void service(HttpServletRequest req, HttpServletResponse resp)     
             throws ServletException, java.io.IOException {     
     
         // 定义图像buffer     
         BufferedImage buffImg = new BufferedImage(width, height,     
                BufferedImage.TYPE_INT_RGB);     
         Graphics2D g = buffImg.createGraphics();     
    
        // 创建一个随机数生成器类     
         Random random = new Random();     
     
         // 将图像填充为白色     
        g.setColor(Color.WHITE);     
         g.fillRect(0, 0, width, height);     
     
        // 创建字体，字体的大小应该根据图片的高度来定。     
         Font font = new Font("Fixedsys", Font.PLAIN, fontHeight);     
         // 设置字体。     
         g.setFont(font);     
    
         // 画边框。     
        g.setColor(Color.BLACK);     
        g.drawRect(0, 0, width - 1, height - 1);     
     
         // 随机产生180条干扰线，使图象中的认证码不易被其它程序探测到。     
         g.setColor(Color.BLACK);     
         for (int i = 0; i < 180; i++) {     
             int x = random.nextInt(width);     
             int y = random.nextInt(height);     
             int xl = random.nextInt(12);     
             int yl = random.nextInt(12);     
             g.drawLine(x, y, x + xl, y + yl);     
         }     
     
         // randomCode用于保存随机产生的验证码     
        StringBuffer randomCode = new StringBuffer();     
         int red = 0, green = 0, blue = 0;     
     
         // 随机产生codeCount数字的验证码。字，字母，颜色都是随机分配的     
         for (int i = 0; i < codeCount; i++) {     
             // 得到随机产生的验证码数字。     
             String strRand = String.valueOf(codeSequence[random.nextInt(codeSequence.length)]);     
             // 产生随机的颜色分量来构造颜色值，这样输出的每位数字的颜色值都将不同。     
             red = random.nextInt(255);     
             green = random.nextInt(255);     
             blue = random.nextInt(255);     
     
             // 用随机产生的颜色将验证码绘制到图像中。     
             g.setColor(new Color(red, green, blue));     
             g.drawString(strRand, (i + 1) * x, codeY);     
     
             // 将产生的四个随机数组合在一起。     
             randomCode.append(strRand);     
         }     
         // 将四位数字的验证码保存到Session中,也可以放到request中     
         HttpSession session = req.getSession();
         session.setAttribute("validateCode", randomCode.toString());     
     
         // 禁止图像缓存。     
         resp.setHeader("Pragma", "no-cache");     
         resp.setHeader("Cache-Control", "no-cache");     
         resp.setDateHeader("Expires", 0);     
     
         resp.setContentType("image/jpeg");     
     
         // 将图像输出到Servlet输出流中。     
         ServletOutputStream sos = resp.getOutputStream();     
         ImageIO.write(buffImg, "jpeg", sos);     
         sos.close();     
     }     
     
}   

2、ResultServlet.java

package verify;


import java.io.IOException;     
import java.io.PrintWriter;     
     
import javax.servlet.ServletException;     
import javax.servlet.http.HttpServlet;     
import javax.servlet.http.HttpServletRequest;     
import javax.servlet.http.HttpServletResponse;     
     
public class ResultServlet extends HttpServlet {

private static final long serialVersionUID = 1L;

     public void doGet(HttpServletRequest request, HttpServletResponse response)     
             throws ServletException, IOException {     
     
         doPost(request, response);     
     }
     public void doPost(HttpServletRequest request, HttpServletResponse response)     
             throws ServletException, IOException { 
         response.setContentType("text/html;charset=utf-8");     
         String validateC = (String) request.getSession().getAttribute("validateCode");     
         String veryCode = request.getParameter("cc");     
         PrintWriter out = response.getWriter();     
         if(veryCode==null||"".equals(veryCode)){     
             out.println("验证码为空");     
         }else{     
             if(validateC.equals(veryCode)){     
                 out.println("验证码正确");     
             }else{     
                 out.println("验证码错误");     
             }     
         }     
         out.flush();     
         out.close();     
    }     
     
}  


3、verifyCode.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">   
        <script type="text/javascript" src="../js/verifyCode.js"></script>   
        <script type="text/javascript" src="../js/jquery.js"></script>   
        <title>test verify code</title>  
        <style type="text/css">
        #infoCode{color:red;font-weight:bold;}
        </style>
    </head>   
    <body>   
        <input id="veryCode" name="veryCode" type="text"/>   
        <img id="imgObj" alt="" src="../verifyCodeServlet"/>   
        <a href="#" onclick="changeImg()" >看不清,换一张</a>   
        <input type="button" value="验证" onclick="checkVerifyCode()"/>   
        <div id="infoCode"></div>   
    </body>   
</html>

4、verifyCode.js

function changeImg(){ 
     var imgSrc = $("#imgObj"); 
     var src = imgSrc.attr("src"); 
     imgSrc.attr("src",chgUrl(src)); 
} 
//为了使每次生成图片不一致，即不让浏览器读缓存，所以需要加上时间戳 
function chgUrl(url){ 
      var timestamp = (new Date()).valueOf();
          url = url + "?tamp=" + timestamp;
      return url; 
  } 
   
function checkVerifyCode(){
      var code = $("#veryCode").attr("value");
      code = "cc=" + code; 
      $.ajax({ 
          type:"POST", 
          url:"../ResultServlet", 
          data:code, 
          success:callback 
      }); 
  } 
   
function callback(data){ 
alert("callback");
      $("#infoCode").html(data); 
  } 

5、web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.4"
xmlns="http://java.sun.com/xml/ns/j2ee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee
http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">
  <servlet>
    <servlet-name>VerifyCodeServlet</servlet-name>
    <servlet-class>verify.VerifyCodeServlet</servlet-class>
  </servlet>
  <servlet>
    <servlet-name>ResultServlet</servlet-name>
    <servlet-class>verify.ResultServlet</servlet-class>
  </servlet>
 
  <servlet-mapping>
    <servlet-name>VerifyCodeServlet</servlet-name>
    <url-pattern>/verifyCodeServlet</url-pattern>
  </servlet-mapping>
  <servlet-mapping>
    <servlet-name>ResultServlet</servlet-name>
    <url-pattern>/ResultServlet</url-pattern>
  </servlet-mapping>
 
  <welcome-file-list>
    <welcome-file>index.jsp</welcome-file>
  </welcome-file-list>
</web-app>