根据url动态生成二维码

 根据url动态生成二维码的工具类，没有细研究，先贴出来，有兴趣自己深究。

public class QRCodeUtil {

    public static BufferedImage createImage(String content, String logoImgPath, boolean needCompress) throws IOException, WriterException {
        Hashtable hints = new Hashtable();
        hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H);
        hints.put(EncodeHintType.CHARACTER_SET, CHARSET);
        hints.put(EncodeHintType.MARGIN, 1);
        //200是定义的二维码或小图片的大小
        BitMatrix bitMatrix = new MultiFormatWriter().encode(content, BarcodeFormat.QR_CODE, 210, 210, hints);
        int width = bitMatrix.getWidth();
        int height = bitMatrix.getHeight();
        BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
        //循环遍历每一个像素点
        for (int x = 0; x < width; x++) {
            for (int y = 0; y < height; y++) {
                image.setRGB(x, y, bitMatrix.get(x, y) ? 0xFF000000 : 0xFFFFFFFF);
            }
        }
        // 没有logo
        if (logoImgPath == null || "".equals(logoImgPath)) {
            return image;
        }

        // 插入logo
        insertImage(image, logoImgPath, needCompress);
        return image;
    }

    private static void insertImage(BufferedImage source, String logoImgPath, boolean needCompress) throws IOException {
        File file = new File(logoImgPath);
        if (!file.exists()) {
            return;
        }

        Image src = ImageIO.read(new File(logoImgPath));
        int width = src.getWidth(null);
        int height = src.getHeight(null);
        //处理logo
        if (needCompress) {
            if (width > WIDTH) {
                width = WIDTH;
            }

            if (height > HEIGHT) {
                height = HEIGHT;
            }

            Image image = src.getScaledInstance(width, height, Image.SCALE_SMOOTH);
            BufferedImage tag = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
            Graphics gMaker = tag.getGraphics();
            gMaker.drawImage(image, 0, 0, null); // 绘制缩小后的图
            gMaker.dispose();
            src = image;
        }

        // 在中心位置插入logo
        Graphics2D graph = source.createGraphics();
        int x = (200 - width) / 2;
        int y = (200 - 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();
    }
}