Use the hutool tool to generate a picture QR code and convert it to base64

   
	/**
	 * 文件BufferedImage类型转BASE64
	 *
	 * @param bufferedImage
	 * @return
	 */
	public static String imageToBase64(BufferedImage bufferedImage) {
    
    
		ByteArrayOutputStream baos = new ByteArrayOutputStream();//io流
		try {
    
    
			ImageIO.write(bufferedImage, "png", baos);//写入流中
		} catch (IOException e) {
    
    
			e.printStackTrace();
		}
		byte[] bytes = baos.toByteArray();//转换成字节
		BASE64Encoder encoder = new BASE64Encoder();
		String png_base64 = encoder.encodeBuffer(bytes).trim();//转换成base64串
		png_base64 = png_base64.replaceAll("\n", "").replaceAll("\r", "");//删除 \r\n
		return "data:image/png;base64," + png_base64;

	}

     /**
     * 文件File类型转BASE64
     *
     * @param file
     * @return
     */
    public static String fileToBase64(File file) {
    
    
        return "data:image/png;base64," + Base64.encodeBase64String(fileToByte(file));
    }
 
    /**
     * 文件File类型转byte[]
     *
     * @param file
     * @return
     */
    private static byte[] fileToByte(File file) {
    
    
        byte[] fileBytes = null;
        FileInputStream fis = null;
        try {
    
    
            fis = new FileInputStream(file);
            fileBytes = new byte[(int) file.length()];
            fis.read(fileBytes);
            fis.close();
        } catch (Exception e) {
    
    
            e.printStackTrace();
        }
        return fileBytes;
    }


  String result=imageToBase64(QrCodeUtil.generate("https://hutool.cn/", 300, 300))