class CaptchaController {
    @Resource(name = "captchaProducer")
    private Producer captchaProducer;

    @Resource(name = "captchaProducerMath")
    private Producer captchaProducerMath;

    @Autowired
    private RedisCache redisCache;
    @Autowired
    private SysConfigService configService;

    /**
     * 生成验证码
     */
    @GetMapping(value = "/captchaImage", name = "生产验证码")
    public R getCode(HttpServletResponse response) throws IOException {<FILL_FUNCTION_BODY>}
}

        R ajax = R.ok();
        boolean captchaEnabled = configService.selectCaptchaEnabled();
        ajax.put("captchaEnabled", captchaEnabled);
        if (!captchaEnabled) {
            return ajax;
        }

        // 保存验证码信息
        String uuid = IdUtils.simpleUUID();
        String verifyKey = CacheConstants.CAPTCHA_CODE_KEY + uuid;

        String capStr = null, code = null;
        BufferedImage image = null;

        String captchaType = ConfigExpander.getLoginCaptchaType();
        if ("math".equals(captchaType)) {
            String capText = captchaProducerMath.createText();
            capStr = capText.substring(0, capText.lastIndexOf("@"));
            code = capText.substring(capText.lastIndexOf("@") + 1);
            image = captchaProducerMath.createImage(capStr);
        } else if ("char".equals(captchaType)) {
            capStr = code = captchaProducer.createText();
            image = captchaProducer.createImage(capStr);
        }

        redisCache.setCacheObject(verifyKey, code, Constants.CAPTCHA_EXPIRATION, TimeUnit.MINUTES);
        // 转换流信息写出
        FastByteArrayOutputStream os = new FastByteArrayOutputStream();
        try {
            ImageIO.write(image, "jpg", os);
        } catch (IOException e) {
            return R.error(e.getMessage());
        }

        ajax.put("uuid", uuid);
        ajax.put("img", Base64.encode(os.toByteArray()));
        return ajax;
    
<no_super_class>