图形验证码组件

柔光的暖阳◎ 2023-06-25 01:59 6阅读 0赞

hutool的验证码已经够用，但有些地方需要自定义（画布超界、去除一些字符），所以对此进行了扩展。

依赖

<dependency>
    			<groupId>cn.hutool</groupId>
    			<artifactId>hutool-all</artifactId>
    			<version>4.5.8</version>
    		</dependency>

生成器

package com.rz.util;
    
    import cn.hutool.captcha.AbstractCaptcha;
    import cn.hutool.captcha.generator.CodeGenerator;
    import cn.hutool.captcha.generator.RandomGenerator;
    import cn.hutool.core.img.GraphicsUtil;
    import cn.hutool.core.img.ImgUtil;
    import cn.hutool.core.util.ObjectUtil;
    import cn.hutool.core.util.RandomUtil;
    
    import java.awt.*;
    import java.awt.image.BufferedImage;
    import java.util.concurrent.ThreadLocalRandom;
    
    /**
     * 自定义验证码生成器（因原生工具经常出现字符超出画布边界，去除一些0和o等字母，特此自定义一个）
     *
     * @author sunziwen
     * @version 1.0
     * @date 2019/9/2 14:24
     **/
    public class BuilderCaptcha extends AbstractCaptcha {
        /**
         * 用于随机选的数字
         */
        private static final String BASE_NUMBER = "123456789";
        /**
         * 用于随机选的字符
         */
        private static final String BASE_CHAR_LOWER = "abcdefghjkmnpqrstuvwxyz";
        private static final String BASE_CHAR_UP = "ABCDEFGHJKMNPQRSTUVWXYZ";
        /**
         * 用于随机选的字符和数字
         */
        private static final String BASE_CHAR_NUMBER = BASE_NUMBER + BASE_CHAR_LOWER + BASE_CHAR_UP;
    
        /**
         * 构造，使用随机验证码生成器生成验证码
         *
         * @param width          图片宽
         * @param height         图片高
         * @param codeCount      字符个数
         * @param interfereCount 验证码干扰元素个数
         */
        public BuilderCaptcha(int width, int height, int codeCount, int interfereCount) {
            super(width, height, new RandomGenerator(BASE_CHAR_NUMBER, codeCount), interfereCount);
        }
    
        /**
         * 根据生成的code创建验证码图片
         *
         * @param code 验证码
         */
        @Override
        protected Image createImage(String code) {
            // 图像buffer
            final BufferedImage image = new BufferedImage(width + 100, height + 50, BufferedImage.TYPE_INT_RGB);
            final Graphics2D g = GraphicsUtil.createGraphics(image, ObjectUtil.defaultIfNull(this.background, Color.WHITE));
    
            // 干扰线
            drawInterfere(g);
    
            // 字符串
            drawString(g, code);
    
            return image;
        }
    
        /**
         * 绘制字符串
         *
         * @param g    {@link Graphics2D}画笔
         * @param code 验证码
         */
        private void drawString(Graphics2D g, String code) {
            // 抗锯齿
            g.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
            // 创建字体
            g.setFont(this.font);
    
            // 文字
            int minY = GraphicsUtil.getMinY(g);
            if (minY < 0) {
                minY = this.height - 1;
            }
    
            final int len = this.generator.getLength();
            int charWidth = width / len;
            for (int i = 0; i < len; i++) {
                // 产生随机的颜色值，让输出的每个字符的颜色值都将不同。
                g.setColor(ImgUtil.randomColor());
                g.drawString(String.valueOf(code.charAt(i)), i * charWidth + 50, RandomUtil.randomInt(minY, this.height));
            }
        }
    
        /**
         * 绘制干扰线
         *
         * @param g {@link Graphics2D}画笔
         */
        private void drawInterfere(Graphics2D g) {
            final ThreadLocalRandom random = RandomUtil.getRandom();
            // 干扰线
            for (int i = 0; i < this.interfereCount; i++) {
                int xs = random.nextInt(width + 200);
                int ys = random.nextInt(height + 100);
                int xe = xs + random.nextInt(width / 8);
                int ye = ys + random.nextInt(height / 8);
                g.setColor(ImgUtil.randomColor(random));
                g.drawLine(xs, ys, xe, ye);
            }
        }
    }

附上一个对应的工具类：

package com.rz.util;
    
    import cn.hutool.core.util.IdUtil;
    import cn.hutool.core.util.StrUtil;
    import com.rz.config.Config;
    import com.rz.utils.RedisUtil;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.stereotype.Component;
    
    import java.util.HashMap;
    
    /**
     * 图形验证码工具类
     *
     * @author sunziwen
     * @version 1.0
     * @date 2019/6/10 10:44
     **/
    @Component
    public class RzCaptchaUtil {
        private RedisUtil redisUtil;
        private Config config;
    
        @Autowired
        public RzCaptchaUtil(RedisUtil redisUtil, Config config) {
            this.redisUtil = redisUtil;
            this.config = config;
        }
    
        /**
         * 获取图形验证码
         *
         * @return
         */
        public HashMap<String, Object> getCaptchaBase64() {
            BuilderCaptcha lineCaptcha = new BuilderCaptcha(config.getCaptchWidth(), config.getCaptchHeight(), 4, 150);
            String imageBase64 = lineCaptcha.getImageBase64();
            String code = lineCaptcha.getCode();
            HashMap<String, Object> hashMap = new HashMap<>(2);
            hashMap.put("captcha", "data:image/png;base64," + imageBase64);
            //存储在redis中的key
            String key = IdUtil.randomUUID() + System.currentTimeMillis();
            hashMap.put("verifyStr", key);
            redisUtil.set(key, code, config.getCaptchExpireTime());
            return hashMap;
        }
    
        /**
         * 校验图形验证码
         *
         * @param code
         * @param verify
         * @return
         */
        public boolean verifyCaptcha(String code, String verify) {
            String redisCode = redisUtil.get(verify) + "";
            if (StrUtil.isNotBlank(code) && StrUtil.equalsIgnoreCase(redisCode, code)) {
                redisUtil.remove(verify);
                return true;
            }
            return false;
        }
    }

使用示例：

@PostMapping(value = "/getCaptcha", name = "获取图形验证码")
        @ApiOperation("获取图形验证码")
        public AppResDto getCaptcha() {
            HashMap<String, Object> hashMap = rzCaptchaUtil.getCaptchaBase64();
            return AppResDto.success(hashMap);
        }
    @ApiOperation("登录")
        @PostMapping("/login")
        @Limit(program = "rz-xxxx", prefix = "users-login", count = 10, period = 30, limitType = LimitType.ANNOTATION)
        public AppResDto login(@RequestParam("phone") @LimitParam String phone,
                               @RequestParam("password") String password,
                               @RequestParam("captcha") String captcha,
                               @RequestParam("verifyStr") String verifyStr) {
            //图形验证码正确
            AssertUtil.isTrue(ResEnums.verify_error, rzCaptchaUtil.verifyCaptcha(captcha, verifyStr));
            return userController.login(phone, password);
        }