登录功能的验证码实现

Controller：　

public class SysLoginController extends AbstractController {

    @Autowired
    private SysCaptchaService sysCaptchaService;
        /**
     * 验证码
     */
    @GetMapping("captcha.jpg")
    public void captcha(HttpServletResponse response, String uuid)throws IOException {

        response.setHeader("Cache-Control", "no-store, no-cache");
        response.setContentType("image/jpeg");

        //获取图片验证码
        BufferedImage image = sysCaptchaService.getCaptcha(uuid);


        ServletOutputStream out = response.getOutputStream();
        //ImageIO 類別的 write() 接受一個 OutputStream 物件，可以將你指定的 BufferedImage 寫入至指定的 OutputStream
        ImageIO.write(image, "jpg", out);


        //优雅的关闭流，只不过commom-io在2.6版本之后，就不使用了（也是jdk7以前）
        IOUtils.closeQuietly(out);
    }
}

SysCaptchaServiceImpl：

/**
 * 验证码
 * @author
 */
@Service("sysCaptchaService")
public class SysCaptchaServiceImpl extends ServiceImpl<SysCaptchaDao, SysCaptchaEntity> implements SysCaptchaService {
    @Autowired
    private Producer producer;

    @Override
    public BufferedImage getCaptcha(String uuid) {

        if(StringUtils.isBlank(uuid)){
            throw new RRException("uuid不能为空");
        }
        //生成文字验证码
        String code = producer.createText();

        SysCaptchaEntity captchaEntity = new SysCaptchaEntity();
        captchaEntity.setUuid(uuid);
        captchaEntity.setCode(code);
        //5分钟后过期
        captchaEntity.setExpireTime(DateUtils.addDateMinutes(new Date(), 5));
        this.save(captchaEntity);
//        System.out.println(captchaEntity);
        //做成的图片大小和样式可以控制吗？还是默认的？
        return producer.createImage(code);
    }

     //登录时验证 
    @Override
    public boolean validate(String uuid, String code) {
        SysCaptchaEntity captchaEntity = this.getOne(new QueryWrapper<SysCaptchaEntity>().eq("uuid", uuid));
        if(captchaEntity == null){
            return false;
        }

        //删除验证码
        this.removeById(uuid);

        if(captchaEntity.getCode().equalsIgnoreCase(code) && captchaEntity.getExpireTime().getTime() >= System.currentTimeMillis()){
            return true;
        }

        return false;
    }
}