用法：
可以直接去官网/p/kaptcha/下载jar，或者在pom.xml中导入
<dependency><groupId>com.google.code.kaptcha</groupId><artifactId>kaptcha</artifactId><version>2.3</version></dependency>
或者（两者选其一即可）
<dependency><groupId>com.github.penggle</groupId><artifactId>kaptcha</artifactId><version>2.3.2</version></dependency>
Kaptcha 详细配置表
业务代码
@Servicepublic class CaptchaService extends BaseService {// 对应CaptchaConfig 定义的bean name@Resource(name = "captchaProducerMath")private Producer captchaProducerMath;@AutowiredRedisOps redisOps;/*** 生成图片验证码*/public DataRespBean<Map<String, Object>> getPictureCaptcha(HttpServletResponse response) throws IOException {String uuid = UUID.randomUUID().toString();String capStr = null, code = null;BufferedImage image = null;// 生成验证码String capText = captchaProducerMath.createText();//截取结果capStr = capText.substring(0, capText.lastIndexOf("@"));code = capText.substring(capText.lastIndexOf("@") + 1);image = captchaProducerMath.createImage(capStr);//结果存入redis,key为uuid 超时时间5分钟redisOps.set(RedisUtil.pictureCaptchaKey(uuid), code, 5 * 60); // 5分钟// 转换流信息写出FastByteArrayOutputStream outputStream= new FastByteArrayOutputStream();Map<String, Object> map = new HashMap<>();try {ImageIO.write(image, "jpg", outputStream);} catch (IOException e) {return new DataRespBean(ResultCodeMsg.SERVER_ERROR.getErrMsg(), e.getMessage());}finally {map.put("uuid", uuid);map.put("img", Base64Encoder.encode(outputStream.toByteArray()));os.close();}return new DataRespBean<>(map);}}
验证码生成规则（根据实际需求修改）
public class KaptchaTextCreator extends DefaultTextCreator {private static final String[] NUMBER= "0,1,2,3,4,5,6,7,8,9,10".split(",");@Overridepublic String getText() {Integer result = 0;//结果Random random = new Random();int x = random.nextInt(10);int y = random.nextInt(10);StringBuilder chinese = new StringBuilder();int randomop = (int) random.nextInt(4)//判断结果生成加减乘除switch (randomoperands){case 0 :result = x * y;chinese.append(NUMBER[x]);chinese.append("*");chinese.append(NUMBER[y]);break;case 1 :if (!x == 0 && y % x == 0) {result = y / x;chinese.append(NUMBER[y]);chinese.append("/");chinese.append(NUMBER[x]);} else {result = x + y;chinese.append(NUMBER[x]);chinese.append("+");chinese.append(NUMBER[y]);}break;case 2 :if (x >= y) {result = x - y;chinese.append(NUMBER[x]);chinese.append("-");chinese.append(NUMBER[y]);} else {result = y - x;chinese.append(NUMBER[y]);chinese.append("-");chinese.append(NUMBER[x]);}break;default:result = x + y;chinese.append(NUMBER[x]);chinese.append("+");chinese.append(NUMBER[y]);}//拼接结果返回suChinese.append("=?@" + result);return suChinese.toString();}
生成图片验证码配置
@Configurationpublic class CaptchaConfig {@Bean(name = "captchaProducerMath")public DefaultKaptcha getKaptchaBeanMath() {DefaultKaptcha defaultKaptcha = new DefaultKaptcha();Properties properties = new Properties();// 图片边框properties.setProperty(KAPTCHA_BORDER, "yes");// 边框颜色properties.setProperty(KAPTCHA_BORDER_COLOR, "105,179,90");// 文本颜色properties.setProperty(KAPTCHA_TEXTPRODUCER_FONT_COLOR, "blue");// 图片宽度 properties.setProperty(KAPTCHA_IMAGE_WIDTH, "130");// 图片高度 properties.setProperty(KAPTCHA_IMAGE_HEIGHT, "32");// 文本字符大小properties.setProperty(KAPTCHA_TEXTPRODUCER_FONT_SIZE, "28");// KAPTCHA_SESSION_KEYproperties.setProperty(KAPTCHA_SESSION_CONFIG_KEY, "KAPTCHA_SESSION_KEY");// 验证码文本生成器properties.setProperty(KAPTCHA_TEXTPRODUCER_IMPL, "对应自己的KaptchaTextCreator 文件路径");// 文本字符间距 properties.setProperty(KAPTCHA_TEXTPRODUCER_CHAR_SPACE, "3");// 文本字符长度properties.setProperty(KAPTCHA_TEXTPRODUCER_CHAR_LENGTH, "6");// 文本字体样式properties.setProperty(KAPTCHA_TEXTPRODUCER_FONT_NAMES, "Arial,Courier");// 干扰颜色properties.setProperty(KAPTCHA_NOISE_COLOR, "white");// 干扰实现类properties.setProperty(KAPTCHA_NOISE_IMPL, "com.google.code.kaptcha.impl.NoNoise");// 图片样式properties.setProperty(KAPTCHA_OBSCURIFICATOR_IMPL, "com.google.code.kaptcha.impl.ShadowGimpy");Config config = new Config(properties);defaultKaptcha.setConfig(config);return defaultKaptcha;}}
返回结果（jpg base64编码）
效果展示
