web项目验证码 *** 最爱那水货

1. jsp代码：

 1 <Script>
 2     function changeImg(){
 3                 document.getElementById("certImg").src ="makeCertPic.jsp?it="+Math.random();  /* +Math.random() */
 4             }
 5 </Script>
 6 
 7 
 8 
 9                         <table width="100%" border="0" cellspacing="1" cellpadding="1">
10                             <tr>
11                                 <td width="5%">&nbsp;</td>
12                                 <td nowrap width="11%" align="left" class="loginname">验证码：
13 
14                                 </td>
15                                 <td nowrap width="68%" class="loginname">
16                                     <div align="left">
17                                         <input type="text" istyle="input01" name="certCode"
18                                             class="input01" />
19                                         <!-- <iframe width="200" height="60" id="certImg" src="makeCertPic.jsp"></iframe> -->
20                                         <img id="certImg" src="makeCertPic.jsp" onclick="changeImg()" alt="看不清换一张">
21                                         <!-- onclick="changeImg()" alt="看不清换一张" -->
22 
23                                     </div>
24 
25                                 </td>
26 
27                             </tr>
28 
29                             <tr>
30                                 <td width="14%">&nbsp;</td>
31 
32                                 <td nowrap width="18%" align="right" class="loginname">
33                                     <div align="left">用户名：</div>
34                                 </td>
35                                 <td nowrap width="68%" class="loginname">
36                                     <div align="left">
37                                         <html:text styleClass="input01" property="user_code"
38                                             onkeypress="return handleEnter(this, event,1)" />
39                                         <!-- <a href="#" onclick="changeImg()">看不清换一张 </a> -->
40                                     </div>
41                                 </td>
42                             </tr>
43                             <tr>
44                                 <td width="14%">&nbsp;</td>
45                                 <td nowrap width="18%" align="right" class="loginname">
46                                     <div align="left">密&nbsp;&nbsp;码：</div>
47                                 </td>
48                                 <td nowrap width="68%" class="loginname">
49                                     <div align="left">
50                                         <html:password styleClass="input01" property="password"
51                                             value="" />
52                                     </div>
53                                 </td>
54 
55                             </tr>
56 
57                             <tr>
58 
59 
60                                 <td align="left">
61                                 <td nowrap align="right"><html:submit value='登　录'
62                                         styleClass="button" onclick="return ck_login();" /></td>
63                                 <td nowrap align="left"><html:reset value='重　写'
64                                         styleClass="button" /></td>
65                                 </td>
66                             </tr>
67                         </table>

2.链接的加jsp文件，用于加载验证码数据

 1 <%@page import="com.test.makeCertPic"%>
 2 <%@ page language="java" import="java.util.*" pageEncoding="GBK"%>
 3 <%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
 4 <%@page contentType="image/jpeg" %>
 5 
 6  <%
 7      makeCertPic pic = new makeCertPic();
 8      String str = pic.getCertPic(0, 0, response.getOutputStream());
 9      session.setAttribute("certCode", str);
10      //关闭response ，不加会运行两次，且会报错
11      out.clear();  
12      out = pageContext.pushBody(); 
13  %>

3.对应的验证码类 java代码

 1 package com.test;
 2 
 3 import java.awt.Color;
 4 import java.awt.Font;
 5 import java.awt.Graphics;
 6 import java.awt.image.BufferedImage;
 7 import java.io.IOException;
 8 import java.io.OutputStream;
 9 import java.util.Random;
10 import javax.imageio.ImageIO;
11 
12 /**
13  * @author dzy 生成验证码图片
14  */
15 public class makeCertPic {
16     // 验证码图片中可以出现的字符集，可根据需要修改
17     private char mapTable[] = { '0','1', '2', '3', '4', '5', '6', '7', '8','9' };
18 
19     /**
20      * 功能:生成彩色验证码图片 参数width为生成图片的宽度,参数height为生成图片的高度,参数os为页面的输出流
21      */
22     public String getCertPic(int width, int height, OutputStream os) {
23         if (width <= 0)
24             width = 60;
25         if (height <= 0)
26             height = 20;
27         BufferedImage image = new BufferedImage(width, height,
28                 BufferedImage.TYPE_INT_RGB);
29         // 获取图形上下文
30         Graphics g = image.getGraphics();
31         // 设定背景色
32         g.setColor(new Color(0xDCDCDC));
33         g.fillRect(0, 0, width, height);
34         // 画边框
35         g.setColor(Color.black);
36         g.drawRect(0, 0, width - 1, height - 1);
37         // 取随机产生的认证码
38         String strEnsure = "";
39         // 4代表4位验证码,如果要生成更多位的认证码,则加大数值
40         for (int i = 0; i < 4; ++i) {
41             strEnsure += mapTable[(int) (mapTable.length * Math.random())];
42         }
43         // 将认证码显示到图像中,如果要生成更多位的认证码,增加drawString语句
44         g.setColor(Color.black);
45         g.setFont(new Font("Atlantic Inline", Font.PLAIN, 18));
46         String str = strEnsure.substring(0, 1);
47         g.drawString(str, 8, 17);
48         str = strEnsure.substring(1, 2);
49         g.drawString(str, 20, 15);
50         str = strEnsure.substring(2, 3);
51         g.drawString(str, 35, 18);
52         str = strEnsure.substring(3, 4);
53         g.drawString(str, 45, 15);
54         // 随机产生10个干扰点
55         Random rand = new Random();
56         for (int i = 0; i < 10; i++) {
57             int x = rand.nextInt(width);
58             int y = rand.nextInt(height);
59             g.drawOval(x, y, 1, 1);
60         }
61         // 释放图形上下文
62         g.dispose();
63         try {
64             // 输出图像到页面 
65             ImageIO.write(image, "JPEG", os);
66         } catch (IOException e) {
67             return "";
68         }
69         return strEnsure;
70     }
71 }

项目中的验证码尤其注意登陆时会被项目的filter类过滤排除，导致验证码加载不出来，需要在web.xml中进行jsp的自定义过滤

本项目中设置filter的xml文件和过滤的java代码如下：

1     <filter>
2         <filter-name>BtSystemFilter</filter-name>
3         <filter-class>com.bettersoft.filters.BtSystemFilter</filter-class>
4     </filter>
5     <filter-mapping>
6         <filter-name>BtSystemFilter</filter-name>
7         <url-pattern>/*</url-pattern>
8     </filter-mapping>

 1 public void doFilter(ServletRequest req, ServletResponse resp, FilterChain chain) throws IOException, ServletException {
 2         HttpServletRequest request = (HttpServletRequest) req;
 3         HttpServletResponse response = (HttpServletResponse) resp;
 4          HttpSession session = request.getSession();
 5         String uri = request.getRequestURI();    
 6          String projectName = request.getContextPath();
 7          String url=uri.substring(projectName.length());
 8         try
 9         {  
10             if( uri.startsWith(projectName + "/services")
11                     || uri.startsWith(projectName + "/axis2-web"))                //webservice
12             {
13                 chain.doFilter(req, resp);
14                 }
15               //过滤.jsp和.do
16             else if (uri.endsWith(".jsp")|| uri.endsWith(".do"))
17             { 
18              //如果为系统登录类型资源不进行session检查    
19              if((uri.equals(projectName+"/index.jsp"))
20                  ||uri.equals(projectName+"/login.jsp")
21                  ||uri.equals(projectName+"/main.jsp")
22                  ||uri.equals(projectName+"/login.do")
23                  ||uri.equals(projectName+"/showTRCA.jsp")//用证书登录时选择证书
24                  ||uri.equals(projectName+"/bindCA.jsp")//用证书登录时绑定证书
25                  ||uri.equals(projectName+"/error.jsp")
26                  ||uri.equals(projectName+"/makeCertPic.jsp")//验证码
27                  )
28              {
29                  chain.doFilter(req, resp); 
30              }    
31              else
32              {   //session失效或未登录
33                  if (session.getAttribute("com.bettersoft.admin.userbean") == null)
34                  { response.sendRedirect(projectName + "/login.jsp?nologin=nologin");
35                   }
36                  else
37                  {   //如果当前资源是系统菜单
38                      if(CheckUserUtil.isSyeRes(url))
39                      {  
40                         if(CheckUserUtil.hasPermission(request, url))
41                         {
42                             chain.doFilter(req, resp);
43                         }
44                         else
45                         {
46                             response.sendRedirect(projectName + "/login.jsp?nologin=invalidurl");    
47                         }    
48                      }    
49                      else
50                      {
51                          chain.doFilter(req, resp);     
52                      }     
53                       
54                  }     
55              }     
56             }else
57             {    
58             chain.doFilter(req, resp); 
59             }
60          }
61         catch(Exception e)
62         {    e.printStackTrace();
63              String  errormsg="未知的系统异常";
64              if(e.getMessage()!=null)
65                  {
66                  //if(e.getMessage().length()<50)
67                  errormsg=e.getMessage();
68                  }
69              request.setAttribute("errormsg",errormsg);
70              request.getRequestDispatcher("/error.jsp").forward(request, response);
71         }
72     }

最后的效果图

web项目 验证码 *** 最爱那水货

1. jsp代码 ：

2.链接的加jsp文件，用于加载验证码数据

3.对应的验证码类 java代码

web项目验证码 *** 最爱那水货

1. jsp代码：