MainActivity

String userAgent = Util.getUserAgent(getApplicationContext(), getApplicationInfo().name);
        ExoDatabaseProvider databaseProvider = new ExoDatabaseProvider(this);
       SimpleCache downloadCache = new SimpleCache(
               Environment.getExternalStorageDirectory(),
                new NoOpCacheEvictor(),
                databaseProvider);
        dataSourceFactory = new DefaultHttpDataSourceFactory(userAgent);
      DownloadManager  downloadManager = new DownloadManager(
                this,
                databaseProvider,
                downloadCache,
                dataSourceFactory);
        byte[] appData = new byte[10];
        DownloadRequest downloadRequest = new DownloadRequest(
                "contentId",
                DownloadRequest.TYPE_PROGRESSIVE,
                Uri.parse("https://mp3melodii.ru/files_site_02/001/standartnyj_signal_sms_iphone.mp3"),
                /* streamKeys= */Collections.<StreamKey>emptyList(), null,appData);
        DownloadService.sendAddDownload(
                this,  ExoDownload.class, downloadRequest, false);