利用hutool工具类，可以很方便生成不同类型的验证码。这里简单记录下使用过程。

一.生成验证码

提供接口将生成的验证码存入session或redis，将验证码以图片格式或者base64编码串返回给调用端。

二.校验验证码

提供接口将收到调用端传过来的校验码，从session或redis取出验证码，两个验证码都全部转小写，进行无大小写区分匹配校验，返回true/flase 。

三.使用案例

1.引入hutool工具类

        <!-- hutool工具类 --><dependency><groupId>cn.hutool</groupId><artifactId>hutool-all</artifactId><version>5.7.12</version></dependency>

2.VerifyCodeResp接口响应体

@Data
public class VerifyCodeResp implements Serializable {/*** header头参数：Captcha-Key*/private String captchaKey;/*** 验证码图片*/private String captchaImg;
}

3.VerifyCodeController验证码工具类

/*** 验证码工具类*/
@RestController
public class VerifyCodeController {@ResourceRedisTemplate<String, String> redisTemplate;/*** 生成验证码** 方法一 ShearCaptcha* 图片格式* session存储* 接口需添加白名单放行** @param request HttpServletRequest*/@GetMapping("/verify")public void verify(HttpServletRequest request, HttpServletResponse response) throws IOException {response.setContentType("image/jpeg");response.setHeader("Pragma", "no-cache");response.setHeader("Cache-Control", "no-cache");response.setDateHeader("Expires", 0);//定义图形验证码的长、宽、验证码字符数、干扰线宽度ShearCaptcha shearCaptcha = CaptchaUtil.createShearCaptcha(150, 40, 5, 4);//图形验证码写出，可以写出到文件，也可以写出到流shearCaptcha.write(response.getOutputStream());//获取验证码中的文字内容request.getSession().setAttribute("verifyCode", shearCaptcha.getCode());}/*** 生成验证码** 方法二 LineCaptcha* 图片格式* session存储* 接口需添加白名单放行** @param request HttpServletRequest*/@GetMapping("/verifyTwo")public void verifyTwo(HttpServletRequest request, HttpServletResponse response) throws IOException {response.setContentType("image/jpeg");response.setHeader("Pragma", "no-cache");response.setHeader("Cache-Control", "no-cache");response.setDateHeader("Expires", 0);//定义图形验证码的长、宽、验证码字符数、干扰线宽度LineCaptcha lineCaptcha = CaptchaUtil.createLineCaptcha(150, 40, 5, 4);//图形验证码写出，可以写出到文件，也可以写出到流ImageIO.write(lineCaptcha.getImage(), "JPEG", response.getOutputStream());//获取验证码中的文字内容request.getSession().setAttribute("verifyCode", lineCaptcha.getCode());}/*** 方法三 ShearCaptcha* 图片的base64编码字符串* session存储* 接口需添加白名单放行** @param request HttpServletRequest* @return String*/@GetMapping("/getVerify")public String getVerify(HttpServletRequest request) {//定义图形验证码的长、宽、验证码字符数、干扰线宽度ShearCaptcha shearCaptcha = CaptchaUtil.createShearCaptcha(150, 40, 5, 4);//获取验证码中的文字内容request.getSession().setAttribute("verifyCode", shearCaptcha.getCode());String base64String = "";try {base64String = "data:image/png;base64," + shearCaptcha.getImageBase64();} catch (Exception e) {e.printStackTrace();}return base64String;}/*** 方法四 LineCaptcha* 图片的base64编码字符串* session存储* 接口需添加白名单放行** @param request HttpServletRequest* @return String*/@GetMapping("/getVerifyTwo")public String getVerifyTwo(HttpServletRequest request) {//定义图形验证码的长、宽、验证码字符数、干扰线宽度LineCaptcha lineCaptcha = CaptchaUtil.createLineCaptcha(150, 40, 5, 4);//获取验证码中的文字内容request.getSession().setAttribute("verifyCode", lineCaptcha.getCode());String base64String = "";try {//返回 base64ByteArrayOutputStream bos = new ByteArrayOutputStream();ImageIO.write(lineCaptcha.getImage(), "JPEG", bos);byte[] bytes = bos.toByteArray();Base64.Encoder encoder = Base64.getEncoder();base64String = "data:image/png;base64," + encoder.encodeToString(bytes);} catch (Exception e) {e.printStackTrace();}return base64String;}/*** 方法五 ShearCaptcha* 图片的base64编码字符串* redis存储* 接口需添加白名单放行** @return String*/@GetMapping("/getVerifyThree")public VerifyCodeResp getVerifyThree() {String captchaKey = UUID.randomUUID().toString();//定义图形验证码的长、宽、验证码字符数、干扰线宽度ShearCaptcha shearCaptcha = CaptchaUtil.createShearCaptcha(150, 40, 5, 0);// 存入redis并设置过期时间为30分钟redisTemplate.opsForValue().set("captcha:" + captchaKey, shearCaptcha.getCode(), 30L, TimeUnit.MINUTES);String base64String = "";try {base64String = "data:image/png;base64," + shearCaptcha.getImageBase64();} catch (Exception e) {e.printStackTrace();}VerifyCodeResp verifyCodeResp = new VerifyCodeResp();verifyCodeResp.setCaptchaKey(captchaKey);verifyCodeResp.setCaptchaImg(base64String);return verifyCodeResp;}/*** 方法六 LineCaptcha* 图片的base64编码字符串* redis存储* 接口需添加白名单放行** @return String*/@GetMapping("/getVerifyFour")public VerifyCodeResp getVerifyFour() {String captchaKey = UUID.randomUUID().toString();//定义图形验证码的长、宽、验证码字符数、干扰线宽度LineCaptcha lineCaptcha = CaptchaUtil.createLineCaptcha(150, 40, 5, 4);// 存入redis并设置过期时间为30分钟redisTemplate.opsForValue().set("captcha:" + captchaKey, lineCaptcha.getCode(), 30L, TimeUnit.MINUTES);String base64String = "";try {//返回 base64ByteArrayOutputStream bos = new ByteArrayOutputStream();ImageIO.write(lineCaptcha.getImage(), "JPEG", bos);byte[] bytes = bos.toByteArray();Base64.Encoder encoder = Base64.getEncoder();base64String = "data:image/png;base64," + encoder.encodeToString(bytes);} catch (Exception e) {e.printStackTrace();}VerifyCodeResp verifyCodeResp = new VerifyCodeResp();verifyCodeResp.setCaptchaKey(captchaKey);verifyCodeResp.setCaptchaImg(base64String);return verifyCodeResp;}
}

4.测试验证

如果测试验证码存入redis，则需要提前配置和启动redis。

5.项目结构及源码下载

下载地址 springboot-cacheable 欢迎star哦~