主要生成几种不同类型的验证码
* 第一种:简单验证码,4位随机数字 :
* 第二种:英文字符加数字的验证码 :
* 第三种:像铁路订票系统一样的验证码,肆+?=21
下面是实现的验证码类,由于我这里是用的SSH2
package com.base.util; import java.awt.Color; import java.awt.Font; import java.awt.Graphics; import java.awt.image.BufferedImage; import java.io.ByteArrayInputStream; import java.io.ByteArrayOutputStream; import java.util.Random; import javax.imageio.ImageIO; import javax.imageio.stream.ImageOutputStream; /** * 验证码类,主要生成几种不同类型的验证码 * 第一种:简单验证码,4位随机数字 * 第二种:英文字符加数字的验证码 * 第三种:像铁路订票系统一样的验证码,肆+?=21 * * @author 李朋飞 * */ public class VerificationCodeUtil { private ByteArrayInputStream image;// 图像 private String str;// 验证码 private static final int WIDTH = 80; private static final int HEIGHT = 20; public static void main(String[] arg) { VerificationCodeUtil vcu = VerificationCodeUtil.Instance(); System.err.println(vcu.getVerificationCodeValue()); } /** * 功能:获取一个验证码类的实例 * * @return */ public static VerificationCodeUtil Instance() { return new VerificationCodeUtil(); } private VerificationCodeUtil() { BufferedImage image = new BufferedImage(WIDTH, HEIGHT, BufferedImage.TYPE_INT_RGB); int randomNum = new Random().nextInt(3); if (randomNum == 0) { initNumVerificationCode(image); } else if (randomNum == 1) { initLetterAndNumVerificationCode(image); } else { initChinesePlusNumVerificationCode(image); } } /** * 功能:设置第一种验证码的属性 */ public void initNumVerificationCode(BufferedImage image) { Random random = new Random(); // 生成随机类 Graphics g = initImage(image, random); 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))); // 调用函数出来的颜色相同,可能是因为种子太接近,所以只能直接生成 g.drawString(rand, 13 * i + 6, 16); } this.setStr(sRand);/* 赋值验证码 */ // 图象生效 g.dispose(); this.setImage(drawImage(image)); } /** * 功能:设置第二种验证码属性 */ public void initLetterAndNumVerificationCode(BufferedImage image) { Random random = new Random(); // 生成随机类 Graphics g = initImage(image, random); String[] letter = { "A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z" }; String sRand = ""; for (int i = 0; i < 4; i++) { String tempRand = ""; if (random.nextBoolean()) { tempRand = String.valueOf(random.nextInt(10)); } else { tempRand = letter[random.nextInt(25)]; if (random.nextBoolean()) {// 随机将该字母变成小写 tempRand = tempRand.toLowerCase(); } } sRand += tempRand; g.setColor(new Color(20 + random.nextInt(10), 20 + random .nextInt(110), 20 + random.nextInt(110))); g.drawString(tempRand, 13 * i + 6, 16); } this.setStr(sRand);/* 赋值验证码 */ g.dispose(); // 图象生效 this.setImage(drawImage(image)); } /** * 功能:设置第三种验证码属性 即:肆+?=24 */ public void initChinesePlusNumVerificationCode(BufferedImage image) { String[] cn = { "壹", "贰", "叁", "肆", "伍", "陆", "柒", "捌", "玖", "拾" }; Random random = new Random(); // 生成随机类 Graphics g = initImage(image, random); int x = random.nextInt(10) + 1; int y = random.nextInt(30); this.setStr(String.valueOf(y)); g.setFont(new Font("楷体", Font.PLAIN, 14));// 设定字体 g.setColor(new Color(20 + random.nextInt(10), 20 + random.nextInt(110), 20 + random.nextInt(110))); g.drawString(cn[x - 1], 1 * 1 + 6, 16); g.drawString("+", 22, 16); g.drawString("?", 35, 16); g.drawString("=", 48, 16); g.drawString(String.valueOf(x + y), 61, 16); g.dispose(); // 图象生效 this.setImage(drawImage(image)); } public Graphics initImage(BufferedImage image, Random random) { Graphics g = image.getGraphics(); // 获取图形上下文 g.setColor(getRandColor(200, 250));// 设定背景色 g.fillRect(0, 0, WIDTH, HEIGHT); g.setFont(new Font("Times New Roman", Font.PLAIN, 14));// 设定字体 g.setColor(getRandColor(160, 200)); // 随机产生165条干扰线,使图象中的认证码不易被其它程序探测到 for (int i = 0; i < 165; 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); } return g; } public ByteArrayInputStream drawImage(BufferedImage image) { ByteArrayInputStream input = null; ByteArrayOutputStream output = new ByteArrayOutputStream(); try { ImageOutputStream imageOut = ImageIO .createImageOutputStream(output); ImageIO.write(image, "JPEG", imageOut); imageOut.close(); input = new ByteArrayInputStream(output.toByteArray()); } catch (Exception e) { System.out.println("验证码图片产生出现错误:" + e.toString()); } return input; } /* * 功能:给定范围获得随机颜色 */ private 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); } /** * 功能:获取验证码的字符串值 * * @return */ public String getVerificationCodeValue() { return this.getStr(); } /** * 功能:取得验证码图片 * * @return */ public ByteArrayInputStream getImage() { return this.image; } public String getStr() { return str; } public void setStr(String str) { this.str = str; } public void setImage(ByteArrayInputStream image) { this.image = image; } }
struts2中获得验证码:
/** * 功能:打开login.jsp的时候获得随机的验证码图片 * * @return */ public String getRandomPictrue() { VerificationCodeUtil vcu = VerificationCodeUtil.Instance(); this.setInputStream(vcu.getImage()); this.setSessionAttribute("random", vcu.getVerificationCodeValue());// 取得随机字符串放入HttpSession return SUCCESS; }
另外前台jsp页面
<script type="text/javascript"> function changeValidateCode(obj) { //获取当前的时间作为参数,无具体意义 var timenow = new Date().getTime(); //每次请求需要一个不同的参数,否则可能会返回同样的验证码 //这和浏览器的缓存机制有关系,也可以把页面设置为不缓存,这样就不用这个参数了。 obj.src="getRandomPictrue?d="+timenow; } </script> <tr> <td height="24" valign="bottom"><div align="right"><span class="STYLE3">验证码</span></div></td> <td width="10" valign="bottom"> </td> <td width="52" height="24" valign="bottom"><input type="text" maxlength=4 name="yzm" id="textfield3" style="width:50px; height:17px; background-color:#87adbf; border:solid 1px #153966; font-size:12px; color:#283439; "></td> <td width="92" valign="bottom"><div align="center"><img src="getRandomPictrue.action" width="80" height="20" onclick="changeValidateCode(this)"></div></td> </tr>
另外,在登录的时候,后台验证验证码是否输入正确
public String userLogin() { String yanzhengma = this.getYzm().toLowerCase();//将验证码字符串全部转换成小写 String random = getSessionAttribute("random").toString().toLowerCase(); if(!yanzhengma.equals(random)){ this.setRequestAttribute("errorMessage", "验证码错误,请核实后重新输入"); return INPUT; } else{ UserModel user = getUserService().loginJudge(getUserName(), getUserPass()); if (user != null) { getSession().setAttribute("user", user); getSession().setAttribute("userId", user.getUserId()); List<PermissionModel> treeList = userService.getTree(user .getUserId()); getRequest().setAttribute("treeList", treeList); this.setRequestAttribute("username", user.getUserName()); user.setLastLoginTime(DateUtil.getCurrentTimestamp()); if (userService.addUser(user)) { logger.info(getUserName() + "登录成功"); return SUCCESS; } else { logger.info(getUserName() + "登录失败,失败原因,更新lastLoginTime失败"); this.setRequestAttribute("errorMessage", "服务器hold不住啦,请稍后重新登录"); return INPUT; } } else { logger.info(getUserName() + "登录失败,用户名或者密码不正确"); this.setRequestAttribute("errorMessage", "登录失败,用户名或者密码不正确"); return INPUT; } } }
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