private void fireOnOptimizeLibraryListener() {
   for (OnLibraryDownloadListener l : listeners) {
     l.OnOptimizeLibrary();
   }
 }
 private void fireOnProgressUpdateListener(int progress) {
   for (OnLibraryDownloadListener l : listeners) {
     l.OnProgressUpdate(progress);
   }
 }
 /*
  * Fire the listeners
  */
 private void fireOnLibraryDownloadFinishedListener(DownloaderResult result) {
   for (OnLibraryDownloadListener l : listeners) {
     l.OnLibraryDownloadFinished(result);
   }
 }