一、处理逻辑图
二、代码部分
项目中封装了Jedis工具类进行redis的数据存取操作，也使用了Cookie工具类进行cookie中的数据存取操作，该篇文件主要介绍验证码校验相关的内容，这里不再介绍java使用Jedis操作redis的方法，如果想了解java使用redis的方法，请参考 这里。
1、前端页面form表单内容
<form action="${request.contextPath}/login"> <div class="login-box-body"> <p class="login-box-msg">统一认证中心</p> <div class="form-group has-feedback"> <input type="text" name="username" class="form-control" placeholder="Please input username." value="user" maxlength="50" > <span class="glyphicon glyphicon-envelope form-control-feedback"></span> </div> <div class="form-group has-feedback"> <input type="password" name="password" class="form-control" placeholder="Please input password." value="123456" maxlength="50" > <span class="glyphicon glyphicon-lock form-control-feedback"></span> </div> <div class="form-group has-feedback"> <input type="vercode" name="vercode" class="form-control" placeholder="Please input vercode." maxlength="50" > <span class="glyphicon glyphicon-lock form-control-feedback"></span> </div> <div> <img src="${request.contextPath}/getCodeImg"> </div> <input type="button" value="看不清? 换一张." id="btn"> <br> <#if errorMsg?exists> <p style="color: red;">${errorMsg}</p> </#if> <div class="row"> <div class="col-xs-8"> <div class="checkbox icheck"> <label> <input type="checkbox" name="ifRemember" >记住密码 </label> </div> </div><!-- /.col --> <div class="col-xs-4"> <input type="hidden" name="redirect_url" value="${redirect_url!''}" /> <button type="submit" class="btn btn-primary btn-block btn-flat">Login</button> </div> </div> </div> </form> 2、后端服务
1、controller代码
@Controller @CrossOrigin public class WebController { /** * 生成验证码 */ public static final String VERIFY_ID = "verid"; @RequestMapping("/getCodeImg") public void getCodeImg(HttpServletRequest request, HttpServletResponse response) { try { Object[] objs = VerifyUtil.createImage(); String code = objs[0].toString(); String verid = UUID.randomUUID().toString().replaceAll("-", ""); Cookie cookie=new Cookie(VERIFY_ID, verid); //将uuid串存入cookie response.addCookie(cookie); StringBuilder verifyKey = new StringBuilder(); verifyKey.append(verid); JedisUtil.setStringValue(verifyKey.toString(), code, 3600); //将验证码存入redis /** * log.info("verid:"+verid); log.info("code:"+code); */ BufferedImage image = (BufferedImage) objs[1]; response.setContentType("image/png"); OutputStream os = response.getOutputStream(); ImageIO.write(image, "png", os); //输出验证码图片文件流 } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } } /** * 登陆验证 */ @RequestMapping(value = "/login",method = RequestMethod.POST) @ResponseBody public LoginResult login(HttpServletRequest request, HttpServletResponse response, @RequestParam("username") String username, @RequestParam("password") String password, @RequestParam("vercode") String vercode) { LoginResult result1=new LoginResult(); //Verification Code if(!StringUtils.hasText(vercode)){ result1.setResultCode(400); result1.setResultMessage("请输入验证码"); return result1; } String verid= CookieUtil.getValue(request,"verid"); //从cookie获取uuid串 String redisVerCode=null; if(StringUtils.hasText(verid)){ redisVerCode= JedisUtil.getStringValue(verid); //从redis获取验证码 JedisUtil.del("verid"+verid); } if(verid==null || redisVerCode==null){ result1.setResultCode(400); result1.setResultMessage("验证码已过期，请刷新验证码"); return result1; } CookieUtil.remove(request,response,"verid"); if(!redisVerCode.equalsIgnoreCase(vercode)){ //比对验证码 result1.setResultCode(ConstantsInit.PARAMS_ERROR); result1.setResultMessage("验证码错误"); return result1; } } 2、验证码生成工具类
public class VerifyUtil { // 验证码字符集 private static final char[] chars = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'j', 'k', 'm', 'n', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'J', 'K', 'L', 'M', 'N', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z' }; // 字符数量 private static final int SIZE = 4; // 干扰线数量 private static final int LINES = 10; // 宽度 private static final int WIDTH = 90; // 高度 private static final int HEIGHT = 40; // 字体大小 private static final int FONT_SIZE = 30; /** * 生成随机验证码及图片 Object[0]：验证码字符串； Object[1]：验证码图片。 */ public static Object[] createImage() { StringBuffer sb = new StringBuffer(); // 1.创建空白图片 BufferedImage image = new BufferedImage(WIDTH, HEIGHT, BufferedImage.TYPE_INT_RGB); // 2.获取图片画笔 Graphics graphic = image.getGraphics(); // 3.设置画笔颜色 graphic.setColor(Color.LIGHT_GRAY); // 4.绘制矩形背景 graphic.fillRect(0, 0, WIDTH, HEIGHT); // 5.画随机字符 Random ran = new Random(); for (int i = 0; i < SIZE; i++) { // 取随机字符索引 int n = ran.nextInt(chars.length); // 设置随机颜色 // graphic.setColor(getRandomColor(101, 111, 121)); graphic.setColor(getRandomColor(150, 150, 150)); // 设置字体大小 graphic.setFont(new Font(null, Font.BOLD + Font.ITALIC, FONT_SIZE)); // 画字符 graphic.drawString(chars[n] + "", i * WIDTH / SIZE, HEIGHT * 2 / 3); // 记录字符 sb.append(chars[n]); } // 6.画干扰线 for (int i = 0; i < LINES; i++) { // 设置随机颜色 graphic.setColor(getRandomColor(255, 255, 255)); // 随机画线 graphic.drawLine(ran.nextInt(WIDTH), ran.nextInt(HEIGHT), ran.nextInt(WIDTH), ran.nextInt(HEIGHT)); } /** * //扭曲 shearX(graphic, WIDTH, HEIGHT, Color.LIGHT_GRAY); shearY(graphic, WIDTH, HEIGHT, Color.LIGHT_GRAY); */ // 7.返回验证码和图片 return new Object[] { sb.toString(), image }; } /** * 随机取色 */ public static Color getRandomColor(int r, int g, int b) { Random ran = new Random(); Color color = new Color(ran.nextInt(r), ran.nextInt(g), ran.nextInt(b)); return color; } /** * fc:110 bc:133 * @param fc * @param bc * @return */ public static Color getRandColor(int fc, int bc) { if (fc > 255) fc = 255; if (bc > 255) bc = 255; Random random = new Random(); int r = fc + random.nextInt(bc - fc - 16); int g = fc + random.nextInt(bc - fc - 14); int b = fc + random.nextInt(bc - fc - 18); return new Color(r, g, b); } private static void shearX(Graphics g, int w1, int h1, Color color) { Random random=new Random(); int period = 2; boolean borderGap = true; int frames = 1; int phase = random.nextInt(2); for (int i = 0; i < h1; i++) { double d = (double) (period >> 1)* Math.sin((double) i / (double) period + (2.2831853071795862D * (double) phase)/ (double) frames); g.copyArea(0, i, w1, 1, (int) d, 0); if (borderGap) { g.setColor(color); g.drawLine((int) d, i, 0, i); g.drawLine((int) d + w1, i, w1, i); } } } private static void shearY(Graphics g, int w1, int h1, Color color) { Random random=new Random(); int period = random.nextInt(40) + 10; // 50; boolean borderGap = true; int frames = 20; int phase = random.nextInt(2); for (int i = 0; i < w1; i++) { double d = (double) (period >> 1) * Math.sin((double) i / (double) period + (2.2831853071795862D * (double) phase)/ (double) frames); g.copyArea(i, 0, 1, h1, 0, (int) d); if (borderGap) { g.setColor(color); g.drawLine(i, (int) d, i, 0); g.drawLine(i, (int) d + h1, i, h1); } } } public static void main(String[] args) throws IOException { Object[] objs = createImage(); BufferedImage image = (BufferedImage) objs[1]; OutputStream os = new FileOutputStream("d:/1.png"); ImageIO.write(image, "png", os); os.close(); } } 文章来源: https://blog.csdn.net/qq_39387856/article/details/88874438