Upload base64 image to Google CDN in Java

/*Upload base64 image in CDN
Save cdn url to database*/

/*
path contain base64 encoded image
(i.e.
Strint path = "data:image/png;base64, iVBORw0KGgoAAAANSUhEUgAAAAUA
    9TXL0Y4OHwAAAABJRU5ErkJggg==";)


*/

class ImageAtCDN{

public String base64ToCDN(String path, String imageName){
 
    int extentionStartIndex = path.indexOf("data:image");
    int extensionEndIndex = path.indexOf(';');
    String fileExtension = path.substring(extentionStartIndex + 11, extensionEndIndex);


        String encodedString = path
        // tokenize the data     
        String parts = encodedString.tokenize(",");
        String imageString = parts[1];

        // create a buffered image     
BufferedImage image
        byte[] imageByte

        BASE64Decoder decoder = new BASE64Decoder();
        imageByte = decoder.decodeBuffer(imageString);
        ByteArrayInputStream bis = new ByteArrayInputStream(imageByte);
        image = ImageIO.read(bis);
        bis.close();

        String uploadFolder = "uploads/shop_instructions";
        String fileName = imageName+"."+ fileExtension;

        // write the image to a file     
 def servletContext = WebUtils.retrieveGrailsWebRequest().getServletContext();
        String imagePath = servletContext.getRealPath(uploadFolder);
        File outputfile = new File(imagePath+"/"+fileName);
        if (!outputfile.exists()) {
            outputfile.mkdirs();
        }
        ImageIO.write(image, fileExtension, outputfile);
        String bucketName = "cdn.xyz.com";
        GoogleFileHelper.uploadFile(uploads/shop_instructions/base/0/0/50/+fileName,outputfile,bucketName);
        if (outputfile.exists()) {
            outputfile.delete()
        }
     
        return path
 
}

}



class GoogleFileHelper{


/*  The below snippets of code will upload the file to the google.    * */


    public static uploadFile(String name,  File file, String bucketName)
            throws IOException, GeneralSecurityException {
/*     The below is the unix command to get the mime type of the file. So below we are using the native command to execute.*/     

 def contentType = file.toURL().openConnection().getContentType()

        println("Content type=="+contentType)

        InputStreamContent contentStream = new InputStreamContent(
                contentType, new FileInputStream(file));

        // Setting the length improves upload performance        contentStream.setLength(file.length());
        StorageObject objectMetadata = new StorageObject()
        // Set the destination object name     
         .setName(name)
        // Set the access control list to publicly read-only             
        .setAcl(Arrays.asList(new ObjectAccessControl().setEntity("allUsers").setRole("READER")));
        // Do the insert     
        Storage client = StorageFactory.getService();
        Storage.Objects.Insert insertRequest = client.objects().insert(bucketName, objectMetadata, contentStream);
        insertRequest.execute();
    }


}