private InputStream downloadFile(String fileName) throws IOException {
File file = DriveUtil.getFileByName(fileName);
if (file.getDownloadUrl() != null && file.getDownloadUrl().length() > 0)
try {
fileSize = file.getFileSize();
return DriveUtil.service.files().get(file.getId()).executeMediaAsInputStream();
} catch (IOException e) {
e.printStackTrace();
MAMUtil.writeLog(e);
return null;
}
return null;
}