一、背景

1.因为最近项目中要更换验证码，用的是kaptch与springboot，操作起来也是比较方便的，也趟了不少弯路，特意记下这个方法，以供大家学习参考，下面我们就来讲解下。

二、项目结构

三、详细的配置

1.pom.xml

<!-- kaptcha  -->
<dependency>
	<groupId>com.google.code</groupId>
	<artifactId>kaptcha</artifactId>
	<version>2.3.2</version>
</dependency>

2.config

2.1.KaptchaConfig.java

@Component
public class KaptchaConfig {
    @Bean
    public DefaultKaptcha getDefaultKaptcha(){
        DefaultKaptcha defaultKaptcha = new DefaultKaptcha();
        Properties properties = new Properties();
        properties.setProperty("kaptcha.border", "no");
        properties.setProperty("kaptcha.border.color", "blue");
        properties.setProperty("kaptcha.textproducer.font.color", "black");
        properties.setProperty("kaptcha.image.width", "160");
        properties.setProperty("kaptcha.image.height", "50");
        properties.setProperty("kaptcha.textproducer.font.size", "40");
        properties.setProperty("kaptcha.session.key", "code");
        properties.setProperty("kaptcha.noise.color", "white");
        properties.setProperty("kaptcha.obscurificator.impl", "com.google.code.kaptcha.impl.ShadowGimpy");
        properties.setProperty("kaptcha.textproducer.char.length", "4");
        properties.setProperty("kaptcha.textproducer.font.names", "宋体,楷体,微软雅黑");
        Config config = new Config(properties);
        defaultKaptcha.setConfig(config);
        return defaultKaptcha;
    }
}

3.controller

3.1.生成验证码的接口（CreateCode.java）

@Controller
@RequestMapping(value = "/createCode")
public class CreateCode {

    @Autowired
    DefaultKaptcha defaultKaptcha;

    @RequestMapping(value="/testdemo", method= RequestMethod.GET)
    public void createCode(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse) throws Exception{
        byte[] captchaChallengeAsJpeg = null;
        ByteArrayOutputStream jpegOutputStream = new ByteArrayOutputStream();
        try {
            //生产验证码字符串并保存到session中去
            String createText = defaultKaptcha.createText();
            //给定一个唯一标识，防止验证码重复使用
            httpServletRequest.getSession().setAttribute(Constants.KAPTCHA_SESSION_KEY, createText);
            //redisCache.set(RedisCache.prefix, coldFlag, createText);
            //使用生产的验证码字符串返回一个BufferedImage对象并转为byte写入到byte数组中
            BufferedImage challenge = defaultKaptcha.createImage(createText);
            ImageIO.write(challenge, "jpg", jpegOutputStream);
        } catch (IllegalArgumentException e) {
            httpServletResponse.sendError(HttpServletResponse.SC_NOT_FOUND);
            return;
        }
        //定义response输出类型为image/jpeg类型，使用response输出流输出图片的byte数组
        captchaChallengeAsJpeg = jpegOutputStream.toByteArray();
        httpServletResponse.setHeader("Cache-Control", "no-store");
        httpServletResponse.setHeader("Pragma", "no-cache");
        httpServletResponse.setDateHeader("Expires", 0);
        httpServletResponse.setContentType("image/jpeg");
        ServletOutputStream responseOutputStream = httpServletResponse.getOutputStream();
        responseOutputStream.write(captchaChallengeAsJpeg);
        responseOutputStream.flush();
        responseOutputStream.close();
    }
}

3.2.postman测试生成验证码

3.3.模拟前端校验验证码（PreCheckController）

@Controller
@RequestMapping(value = "/preCheckCode")
@Slf4j
public class PreCheckController {
    //验证码验证
    @PostMapping("/checkCode")
    @ResponseBody
    public String imgvrifyControllerDefaultKaptcha(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse,@RequestBody JSONObject data){
        String captchaId = (String) httpServletRequest.getSession().getAttribute(Constants.KAPTCHA_SESSION_KEY);
        String code = data.getString("code");
        log.info("Session  vrifyCode ---->"+captchaId+"---- form code --->"+code);
        if (!captchaId.equals(code)) {
            log.info("错误的验证码");
            return "fail";
        } else {
            return "success";
        }
    }
}

3.4.模拟前端postman测试

四、看后端日志

1.日志，前端输入的和我们保存在session中的是一致的

五、总结

1.这样就完成了验证码的生成以及校验，希望能帮助到你们，共勉！！！