spring boot 整合zxing生成二维码

1. 引入zxing依赖：

<dependency>
  <groupId>com.google.zxing</groupId>
    <artifactId>core</artifactId>
</dependency>
<dependency>
    <groupId>com.google.zxing</groupId>
    <artifactId>javase</artifactId>
</dependency>

2. 二维码生成工具类

public class QRCodeUtil {
    private QRCodeUtil(){}
    /**
     * 编码格式,采用utf-8
     */
    private static final String UNICODE = "utf-8";
    /**
     * 图片格式
     */
    private static final String FORMAT = "JPG";
    /**
     * 二维码宽度,单位：像素pixels
     */
    private static final int QRCODE_WIDTH = 300;
    /**
     * 二维码高度,单位：像素pixels
     */
    private static final int QRCODE_HEIGHT = 300;
    /**
     * LOGO宽度,单位：像素pixels
     */
    private static final int LOGO_WIDTH = 100;
    /**
     * LOGO高度,单位：像素pixels
     */
    private static final int LOGO_HEIGHT = 100;

    /**
     * 生成二维码图片
     * @param content 二维码内容
     * @param logoPath 图片地址
     * @param needCompress 是否压缩
     * @return
     * @throws Exception
     */
    private static BufferedImage createImage(String content, String logoPath, boolean needCompress) throws IOException, WriterException {
        HashMap<EncodeHintType, Object> hints = new HashMap<>(8);
        hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H);
        hints.put(EncodeHintType.CHARACTER_SET, UNICODE);
        hints.put(EncodeHintType.MARGIN, 1);
        BitMatrix bitMatrix = new MultiFormatWriter().encode(content, BarcodeFormat.QR_CODE, QRCODE_WIDTH, QRCODE_HEIGHT,
                hints);
        int width = bitMatrix.getWidth();
        int height = bitMatrix.getHeight();
        BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
        for (int x = 0; x < width; x++) {
            for (int y = 0; y < height; y++) {
                image.setRGB(x, y, bitMatrix.get(x, y) ? 0xFF000000 : 0xFFFFFFFF);
            }
        }
        if (logoPath == null || "".equals(logoPath)) {
            return image;
        }
        // 插入图片
        QRCodeUtil.insertImage(image, logoPath, needCompress);
        return image;
    }

    /**
     * 插入LOGO
     * @param source 二维码图片
     * @param logoPath LOGO图片地址
     * @param needCompress 是否压缩
     * @throws Exception
     */
    private static void insertImage(BufferedImage source, String logoPath, boolean needCompress) throws IOException {
        File file = new File(logoPath);
        if (!file.exists()) {
            throw new IOException("logo file not found.");
        }
        Image src = ImageIO.read(new File(logoPath));
        int width = src.getWidth(null);
        int height = src.getHeight(null);
        // 压缩LOGO
        if (needCompress) {
            if (width > LOGO_WIDTH) {
                width = LOGO_WIDTH;
            }
            if (height > LOGO_HEIGHT) {
                height = LOGO_HEIGHT;
            }
            Image image = src.getScaledInstance(width, height, Image.SCALE_SMOOTH);
            BufferedImage tag = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
            Graphics g = tag.getGraphics();
            // 绘制缩小后的图
            g.drawImage(image, 0, 0, null);
            g.dispose();
            src = image;
        }
        // 插入LOGO
        Graphics2D graph = source.createGraphics();
        int x = (QRCODE_WIDTH - width) / 2;
        int y = (QRCODE_HEIGHT - height) / 2;
        graph.drawImage(src, x, y, width, height, null);
        Shape shape = new RoundRectangle2D.Float(x, y, width, width, 6, 6);
        graph.setStroke(new BasicStroke(3f));
        graph.draw(shape);
        graph.dispose();
    }

    /**
     * 生成二维码(内嵌LOGO)
     * 调用者指定二维码文件名
     * @param content 二维码的内容
     * @param logoPath 中间图片地址
     * @param destPath 存储路径
     * @param fileName 文件名称
     * @param needCompress 是否压缩
     * @return
     * @throws Exception
     */
    public static String encode(String content, String logoPath, String destPath, String fileName, boolean needCompress) throws IOException, WriterException {
        BufferedImage image = QRCodeUtil.createImage(content, logoPath, needCompress);
        mkdirs(destPath);
        //文件名称通过传递
        fileName = fileName.substring(0, fileName.indexOf('.') != -1 ? fileName.indexOf('.'):fileName.length())
                + "." + FORMAT.toLowerCase();
        ImageIO.write(image, FORMAT, new File(destPath + fileName));
        return fileName;
    }

    /**
     * 创建文件夹， mkdirs会自动创建多层目录，区别于mkdir．(mkdir如果父目录不存在则会抛出异常)
     * @param destPath
     */
    public static void mkdirs(String destPath) throws IOException {
        File file = new File(destPath);
        if (!file.exists() && !file.isDirectory()) {
            boolean isOK = file.mkdirs();
            if (!isOK){
                throw new IOException("生成二维码暂存文件夹失败");
            }
        }
    }

    /**
     * 解析二维码
     * @param path 二维码图片路径
     * @return String 二维码内容
     * @throws Exception
     */
    public static String decode(String path) throws IOException, NotFoundException {
        File file = new File(path);
        BufferedImage image = ImageIO.read(file);
        if (image == null) {
            return null;
        }
        BufferedImageLuminanceSource source = new BufferedImageLuminanceSource(image);
        BinaryBitmap bitmap = new BinaryBitmap(new HybridBinarizer(source));
        Result result;
        HashMap<DecodeHintType, Object> hints = new HashMap<>(8);
        hints.put(DecodeHintType.CHARACTER_SET, UNICODE);
        result = new MultiFormatReader().decode(bitmap, hints);
        return result.getText();
    }

}