Java生成二维码的具体实现方法

1、首先导入需要使用的工具类

    <dependency>
      <groupId>com.google.zxing</groupId>
      <artifactId>core</artifactId>
      <version>3.3.3</version>
    </dependency>

    <dependency>
      <groupId>org.jodd</groupId>
      <artifactId>jodd-core</artifactId>
      <version>5.1.5</version> <!-- 根据你需要的版本进行修改 -->
    </dependency>

2、设置二维码的参数格式

    /**
     * 设置二维码的格式参数
     * @return
     */
    private static Map<EncodeHintType, Object> getDecodeHintType() {
        // 用于设置QR二维码参数
        Map<EncodeHintType, Object> hints = new HashMap<EncodeHintType, Object>();
        // 设置QR二维码的纠错级别（H为最高级别）具体级别信息
        hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H);
        // 设置编码方式
        hints.put(EncodeHintType.CHARACTER_SET, "utf-8");
        hints.put(EncodeHintType.MARGIN, 0);
        hints.put(EncodeHintType.MAX_SIZE, 350);
        hints.put(EncodeHintType.MIN_SIZE, 100);
        return hints;
    }

3、生成二维码的具体方法

    /**
     * @Author: jiang5sx
     * @Description: 生成普通的二维码
     * @Date:
     */
    public static BufferedImage createCode(String qrUrl) {
        MultiFormatWriter multiFormatWriter = null;
        BitMatrix bm = null;
        BufferedImage image = null;
        Map<EncodeHintType, Object> hints = getDecodeHintType();
        try {
            multiFormatWriter = new MultiFormatWriter();
            // 参数顺序分别为：编码内容，编码类型，生成图片宽度，生成图片高度，设置参数
            bm = multiFormatWriter.encode(qrUrl, BarcodeFormat.QR_CODE, width, height, hints);
            int w = bm.getWidth();
            int h = bm.getHeight();
            image = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB);

            // 开始利用二维码数据创建Bitmap图片，分别设为黑（0xFFFFFFFF）白（0xFF000000）两色
            for (int x = 0; x < w; x++) {
                for (int y = 0; y < h; y++) {
                    image.setRGB(x, y, bm.get(x, y) ? QRCOLOR : BGCOLOR);
                }
            }
        } catch (WriterException e) {
            e.printStackTrace();
        }
        return image;
    }

4、调用并成功二维码

public class Test{
        public static void main(String[] args) throws IOException {
        //text要生成内容
        String text = "https://blog.youkuaiyun.com/m0_48952989/article/details/128376479?spm=1001.2014.3001.5501";
        BufferedImage bufferedImage = createCode(text);
        String fileName  = "qrcode.png";
        //filePath 保存的路径
        String filePath = "D:\\" + fileName;
        File file = new File(filePath);
        ImageIO.write(bufferedImage, "png", file);
    }
}

5、运行结果

6、扩展：生成带log的二维码

    /**
     * @Author:jiang5sx
     * @Description: 生成带logo的二维码
     * @Date:
     */
    public static BufferedImage createCodeWithLogo(String qrUrl, String logoPath) {
        BufferedImage bim = createCode(qrUrl);
        try {
            // 读取二维码图片，并构建绘图对象
            Graphics2D g = bim.createGraphics();

            // 读取Logo图片
            BufferedImage logo = ImageIO.read(new File(logoPath));
            //设置logo的大小,这里设置为二维码图片的20%,过大会盖掉二维码
            int widthLogo = Math.min(logo.getWidth(null), bim.getWidth() * 3 / 10),
                    heightLogo = logo.getHeight(null) > bim.getHeight() * 3 / 10 ? (bim.getHeight() * 3 / 10) : logo.getWidth(null);

            // logo放在中心
            int x = (bim.getWidth() - widthLogo) / 2;
            int y = (bim.getHeight() - heightLogo) / 2;
            // logo放在右下角
            // int x = (image.getWidth() - widthLogo);
            // int y = (image.getHeight() - heightLogo);

            //开始绘制图片
            g.drawImage(logo, x, y, widthLogo, heightLogo, null);
            g.dispose();
            logo.flush();
            bim.flush();
            return bim;
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }

7、运行结果