Comment télécharger le fichier PDF à partir du stockage Firebase et enregistrer dans un stockage privé externe dans Android

public long downloadFile(Context context, String fileName, String fileExtension, String destinationDirectory, String url) {


     DownloadManager downloadmanager = (DownloadManager) context.
            getSystemService(Context.DOWNLOAD_SERVICE);
     Uri uri = Uri.parse(url);
     DownloadManager.Request request = new DownloadManager.Request(uri);

     request.setNotificationVisibility(DownloadManager.Request.VISIBILITY_VISIBLE_NOTIFY_COMPLETED);
     request.setDestinationInExternalFilesDir(context, destinationDirectory, fileName + fileExtension);

     return downloadmanager.enqueue(request);
}
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