com.google.android.exoplayer2.upstream.cache.Cache Java Examples

/**
 * 根据缓存块判断是否缓存成功
 *
 * @param cache
 */
private static boolean resolveCacheState(Cache cache, String url) {
    boolean isCache = true;
    if (!TextUtils.isEmpty(url)) {
        String key = CacheUtil.generateKey(Uri.parse(url));
        if (!TextUtils.isEmpty(key)) {
            NavigableSet<CacheSpan> cachedSpans = cache.getCachedSpans(key);
            if (cachedSpans.size() == 0) {
                isCache = false;
            } else {
                long contentLength = cache.getContentMetadata(key).get(ContentMetadata.KEY_CONTENT_LENGTH, C.LENGTH_UNSET);
                long currentLength = 0;
                for (CacheSpan cachedSpan : cachedSpans) {
                    currentLength += cache.getCachedLength(key, cachedSpan.position, cachedSpan.length);
                }
                isCache = currentLength >= contentLength;
            }
        } else {
            isCache = false;
        }
    }
    return isCache;
}
 

/**
 * Cache需要release之后才能clear
 *
 * @param context
 * @param cacheDir
 * @param url
 */
public static void clearCache(Context context, File cacheDir, String url) {
    try {
        Cache cache = getCacheSingleInstance(context, cacheDir);
        if (!TextUtils.isEmpty(url)) {
            if (cache != null) {
                CacheUtil.remove(cache, CacheUtil.generateKey(Uri.parse(url)));
            }
        } else {
            if (cache != null) {
                for (String key : cache.getKeys()) {
                    CacheUtil.remove(cache, key);
                }
            }
        }
    } catch (Exception e) {
        e.printStackTrace();
    }
}
 

/**
 * @param cache Cache instance to be used to store downloaded data.
 * @param upstreamFactory A {@link DataSource.Factory} for creating {@link DataSource}s for
 *     downloading data.
 */
public DownloaderConstructorHelper(Cache cache, DataSource.Factory upstreamFactory) {
  this(
      cache,
      upstreamFactory,
      /* cacheReadDataSourceFactory= */ null,
      /* cacheWriteDataSinkFactory= */ null,
      /* priorityTaskManager= */ null);
}
 

/**
 * @param cache Cache instance to be used to store downloaded data.
 * @param upstreamFactory A {@link DataSource.Factory} for creating {@link DataSource}s for
 *     downloading data.
 * @param cacheReadDataSourceFactory A {@link DataSource.Factory} for creating {@link DataSource}s
 *     for reading data from the cache. If null then a {@link FileDataSource.Factory} will be
 *     used.
 * @param cacheWriteDataSinkFactory A {@link DataSink.Factory} for creating {@link DataSource}s
 *     for writing data to the cache. If null then a {@link CacheDataSinkFactory} will be used.
 * @param priorityTaskManager A {@link PriorityTaskManager} to use when downloading. If non-null,
 *     downloaders will register as tasks with priority {@link C#PRIORITY_DOWNLOAD} whilst
 *     downloading.
 */
public DownloaderConstructorHelper(
    Cache cache,
    DataSource.Factory upstreamFactory,
    @Nullable DataSource.Factory cacheReadDataSourceFactory,
    @Nullable DataSink.Factory cacheWriteDataSinkFactory,
    @Nullable PriorityTaskManager priorityTaskManager) {
  this(
      cache,
      upstreamFactory,
      cacheReadDataSourceFactory,
      cacheWriteDataSinkFactory,
      priorityTaskManager,
      /* cacheKeyFactory= */ null);
}
 

/**
 * @param cache Cache instance to be used to store downloaded data.
 * @param upstreamFactory A {@link DataSource.Factory} for creating {@link DataSource}s for
 *     downloading data.
 * @param cacheReadDataSourceFactory A {@link DataSource.Factory} for creating {@link DataSource}s
 *     for reading data from the cache. If null then a {@link FileDataSourceFactory} will be used.
 * @param cacheWriteDataSinkFactory A {@link DataSink.Factory} for creating {@link DataSource}s
 *     for writing data to the cache. If null then a {@link CacheDataSinkFactory} will be used.
 * @param priorityTaskManager A {@link PriorityTaskManager} to use when downloading. If non-null,
 *     downloaders will register as tasks with priority {@link C#PRIORITY_DOWNLOAD} whilst
 *     downloading.
 */
public DownloaderConstructorHelper(
    Cache cache,
    DataSource.Factory upstreamFactory,
    @Nullable DataSource.Factory cacheReadDataSourceFactory,
    @Nullable DataSink.Factory cacheWriteDataSinkFactory,
    @Nullable PriorityTaskManager priorityTaskManager) {
  this(
      cache,
      upstreamFactory,
      cacheReadDataSourceFactory,
      cacheWriteDataSinkFactory,
      priorityTaskManager,
      /* cacheKeyFactory= */ null);
}
 

/**
 * Creates a {@link DownloadManager}.
 *
 * @param cache Cache instance to be used to store downloaded data.
 * @param upstreamDataSourceFactory A {@link DataSource.Factory} for creating data sources for
 *     downloading upstream data.
 * @param actionSaveFile File to save active actions.
 * @param deserializers Used to deserialize {@link DownloadAction}s. If empty, {@link
 *     DownloadAction#getDefaultDeserializers()} is used instead.
 */
public DownloadManager(
    Cache cache,
    DataSource.Factory upstreamDataSourceFactory,
    File actionSaveFile,
    Deserializer... deserializers) {
  this(
      new DownloaderConstructorHelper(cache, upstreamDataSourceFactory),
      actionSaveFile,
      deserializers);
}
 

/**
 * @param cache Cache instance to be used to store downloaded data.
 * @param upstreamFactory A {@link DataSource.Factory} for creating {@link DataSource}s for
 *     downloading data.
 */
public DownloaderConstructorHelper(Cache cache, DataSource.Factory upstreamFactory) {
  this(
      cache,
      upstreamFactory,
      /* cacheReadDataSourceFactory= */ null,
      /* cacheWriteDataSinkFactory= */ null,
      /* priorityTaskManager= */ null);
}
 

/**
 * @param cache Cache instance to be used to store downloaded data.
 * @param upstreamDataSourceFactory A {@link Factory} for downloading data.
 * @param cacheReadDataSourceFactory A {@link Factory} for reading data from the cache. If null
 *     then standard {@link FileDataSource} instances will be used.
 * @param cacheWriteDataSinkFactory A {@link DataSink.Factory} for writing data to the cache. If
 *     null then standard {@link CacheDataSink} instances will be used.
 * @param priorityTaskManager A {@link PriorityTaskManager} to use when downloading. If non-null,
 *     downloaders will register as tasks with priority {@link C#PRIORITY_DOWNLOAD} whilst
 *     downloading.
 */
public DownloaderConstructorHelper(
    Cache cache,
    Factory upstreamDataSourceFactory,
    @Nullable Factory cacheReadDataSourceFactory,
    @Nullable DataSink.Factory cacheWriteDataSinkFactory,
    @Nullable PriorityTaskManager priorityTaskManager) {
  Assertions.checkNotNull(upstreamDataSourceFactory);
  this.cache = cache;
  this.upstreamDataSourceFactory = upstreamDataSourceFactory;
  this.cacheReadDataSourceFactory = cacheReadDataSourceFactory;
  this.cacheWriteDataSinkFactory = cacheWriteDataSinkFactory;
  this.priorityTaskManager = priorityTaskManager;
}
 

/**
 * @param cache Cache instance to be used to store downloaded data.
 * @param upstreamFactory A {@link DataSource.Factory} for creating {@link DataSource}s for
 *     downloading data.
 * @param cacheReadDataSourceFactory A {@link DataSource.Factory} for creating {@link DataSource}s
 *     for reading data from the cache. If null then a {@link FileDataSourceFactory} will be used.
 * @param cacheWriteDataSinkFactory A {@link DataSink.Factory} for creating {@link DataSource}s
 *     for writing data to the cache. If null then a {@link CacheDataSinkFactory} will be used.
 * @param priorityTaskManager A {@link PriorityTaskManager} to use when downloading. If non-null,
 *     downloaders will register as tasks with priority {@link C#PRIORITY_DOWNLOAD} whilst
 *     downloading.
 */
public DownloaderConstructorHelper(
    Cache cache,
    DataSource.Factory upstreamFactory,
    @Nullable DataSource.Factory cacheReadDataSourceFactory,
    @Nullable DataSink.Factory cacheWriteDataSinkFactory,
    @Nullable PriorityTaskManager priorityTaskManager) {
  this(
      cache,
      upstreamFactory,
      cacheReadDataSourceFactory,
      cacheWriteDataSinkFactory,
      priorityTaskManager,
      /* cacheKeyFactory= */ null);
}
 

/**
 * Creates a {@link DownloadManager}.
 *
 * @param cache Cache instance to be used to store downloaded data.
 * @param upstreamDataSourceFactory A {@link DataSource.Factory} for creating data sources for
 *     downloading upstream data.
 * @param actionSaveFile File to save active actions.
 * @param deserializers Used to deserialize {@link DownloadAction}s. If empty, {@link
 *     DownloadAction#getDefaultDeserializers()} is used instead.
 */
public DownloadManager(
    Cache cache,
    DataSource.Factory upstreamDataSourceFactory,
    File actionSaveFile,
    Deserializer... deserializers) {
  this(
      new DownloaderConstructorHelper(cache, upstreamDataSourceFactory),
      actionSaveFile,
      deserializers);
}
 

/**
 * @param cache Cache instance to be used to store downloaded data.
 * @param upstreamFactory A {@link DataSource.Factory} for creating {@link DataSource}s for
 *     downloading data.
 */
public DownloaderConstructorHelper(Cache cache, DataSource.Factory upstreamFactory) {
  this(
      cache,
      upstreamFactory,
      /* cacheReadDataSourceFactory= */ null,
      /* cacheWriteDataSinkFactory= */ null,
      /* priorityTaskManager= */ null);
}
 

/**
 * @param cache Cache instance to be used to store downloaded data.
 * @param upstreamDataSourceFactory A {@link Factory} for downloading data.
 * @param cacheReadDataSourceFactory A {@link Factory} for reading data from the cache. If null
 *     then standard {@link FileDataSource} instances will be used.
 * @param cacheWriteDataSinkFactory A {@link DataSink.Factory} for writing data to the cache. If
 *     null then standard {@link CacheDataSink} instances will be used.
 * @param priorityTaskManager A {@link PriorityTaskManager} to use when downloading. If non-null,
 *     downloaders will register as tasks with priority {@link C#PRIORITY_DOWNLOAD} whilst
 *     downloading.
 */
public DownloaderConstructorHelper(
    Cache cache,
    Factory upstreamDataSourceFactory,
    @Nullable Factory cacheReadDataSourceFactory,
    @Nullable DataSink.Factory cacheWriteDataSinkFactory,
    @Nullable PriorityTaskManager priorityTaskManager) {
  Assertions.checkNotNull(upstreamDataSourceFactory);
  this.cache = cache;
  this.upstreamDataSourceFactory = upstreamDataSourceFactory;
  this.cacheReadDataSourceFactory = cacheReadDataSourceFactory;
  this.cacheWriteDataSinkFactory = cacheWriteDataSinkFactory;
  this.priorityTaskManager = priorityTaskManager;
}
 

/**
 * 获取SourceFactory，是否带Cache
 */
private DataSource.Factory getDataSourceFactoryCache(Context context, boolean cacheEnable, boolean preview, File cacheDir, String uerAgent) {
    if (cacheEnable) {
        Cache cache = getCacheSingleInstance(context, cacheDir);
        if (cache != null) {
            isCached = resolveCacheState(cache, mDataSource);
            return new CacheDataSourceFactory(cache, getDataSourceFactory(context, preview, uerAgent), CacheDataSource.FLAG_IGNORE_CACHE_ON_ERROR);
        }
    }
    return getDataSourceFactory(context, preview, uerAgent);
}
 

/** Returns the {@link Cache} instance. */
public Cache getCache() {
  return cache;
}
 

/** Returns the {@link Cache} instance. */
public Cache getCache() {
  return cache;
}
 

@Parameterized.Parameters(name = "{0} with detail {1} is mapped from {2}")
public static Collection<Object[]> parameters() {
    return Arrays.asList(
            new Object[]{SOURCE, SAMPLE_QUEUE_MAPPING_ERROR, createSource(new SampleQueueMappingException("mimetype-sample"))},
            new Object[]{SOURCE, READING_LOCAL_FILE_ERROR, createSource(new FileDataSource.FileDataSourceException(new IOException()))},
            new Object[]{SOURCE, UNEXPECTED_LOADING_ERROR, createSource(new Loader.UnexpectedLoaderException(new Throwable()))},
            new Object[]{SOURCE, LIVE_STALE_MANIFEST_AND_NEW_MANIFEST_COULD_NOT_LOAD_ERROR, createSource(new DashManifestStaleException())},
            new Object[]{SOURCE, DOWNLOAD_ERROR, createSource(new DownloadException("download-exception"))},
            new Object[]{SOURCE, AD_LOAD_ERROR_THEN_WILL_SKIP, createSource(AdsMediaSource.AdLoadException.createForAd(new Exception()))},
            new Object[]{SOURCE, AD_GROUP_LOAD_ERROR_THEN_WILL_SKIP, createSource(AdsMediaSource.AdLoadException.createForAdGroup(new Exception(), 0))},
            new Object[]{SOURCE, ALL_ADS_LOAD_ERROR_THEN_WILL_SKIP, createSource(AdsMediaSource.AdLoadException.createForAllAds(new Exception()))},
            new Object[]{SOURCE, ADS_LOAD_UNEXPECTED_ERROR_THEN_WILL_SKIP, createSource(AdsMediaSource.AdLoadException.createForUnexpected(new RuntimeException()))},
            new Object[]{SOURCE, MERGING_MEDIA_SOURCE_CANNOT_MERGE_ITS_SOURCES, createSource(new MergingMediaSource.IllegalMergeException(MergingMediaSource.IllegalMergeException.REASON_PERIOD_COUNT_MISMATCH))},
            new Object[]{SOURCE, CLIPPING_MEDIA_SOURCE_CANNOT_CLIP_WRAPPED_SOURCE_INVALID_PERIOD_COUNT, createSource(new ClippingMediaSource.IllegalClippingException(ClippingMediaSource.IllegalClippingException.REASON_INVALID_PERIOD_COUNT))},
            new Object[]{SOURCE, CLIPPING_MEDIA_SOURCE_CANNOT_CLIP_WRAPPED_SOURCE_NOT_SEEKABLE_TO_START, createSource(new ClippingMediaSource.IllegalClippingException(ClippingMediaSource.IllegalClippingException.REASON_NOT_SEEKABLE_TO_START))},
            new Object[]{SOURCE, CLIPPING_MEDIA_SOURCE_CANNOT_CLIP_WRAPPED_SOURCE_INVALID_PERIOD_COUNT, createSource(new ClippingMediaSource.IllegalClippingException(ClippingMediaSource.IllegalClippingException.REASON_INVALID_PERIOD_COUNT))},
            new Object[]{SOURCE, TASK_CANNOT_PROCEED_PRIORITY_TOO_LOW, createSource(new PriorityTaskManager.PriorityTooLowException(1, 2))},
            new Object[]{SOURCE, PARSING_MEDIA_DATA_OR_METADATA_ERROR, createSource(new ParserException())},
            new Object[]{SOURCE, CACHE_WRITING_DATA_ERROR, createSource(new Cache.CacheException("cache-exception"))},
            new Object[]{SOURCE, READ_LOCAL_ASSET_ERROR, createSource(new AssetDataSource.AssetDataSourceException(new IOException()))},
            new Object[]{SOURCE, DATA_POSITION_OUT_OF_RANGE_ERROR, createSource(new DataSourceException(DataSourceException.POSITION_OUT_OF_RANGE))},

            new Object[]{CONNECTIVITY, HTTP_CANNOT_OPEN_ERROR, createSource(new HttpDataSource.HttpDataSourceException(new DataSpec(Uri.EMPTY, 0), HttpDataSource.HttpDataSourceException.TYPE_OPEN))},
            new Object[]{CONNECTIVITY, HTTP_CANNOT_READ_ERROR, createSource(new HttpDataSource.HttpDataSourceException(new DataSpec(Uri.EMPTY, 0), HttpDataSource.HttpDataSourceException.TYPE_READ))},
            new Object[]{CONNECTIVITY, HTTP_CANNOT_CLOSE_ERROR, createSource(new HttpDataSource.HttpDataSourceException(new DataSpec(Uri.EMPTY, 0), HttpDataSource.HttpDataSourceException.TYPE_CLOSE))},
            new Object[]{CONNECTIVITY, READ_CONTENT_URI_ERROR, createSource(new ContentDataSource.ContentDataSourceException(new IOException()))},
            new Object[]{CONNECTIVITY, READ_FROM_UDP_ERROR, createSource(new UdpDataSource.UdpDataSourceException(new IOException()))},

            new Object[]{RENDERER_DECODER, AUDIO_SINK_CONFIGURATION_ERROR, createRenderer(new AudioSink.ConfigurationException("configuration-exception"))},
            new Object[]{RENDERER_DECODER, AUDIO_SINK_INITIALISATION_ERROR, createRenderer(new AudioSink.InitializationException(0, 0, 0, 0))},
            new Object[]{RENDERER_DECODER, AUDIO_SINK_WRITE_ERROR, createRenderer(new AudioSink.WriteException(0))},
            new Object[]{RENDERER_DECODER, AUDIO_UNHANDLED_FORMAT_ERROR, createRenderer(new AudioProcessor.UnhandledFormatException(0, 0, 0))},
            new Object[]{RENDERER_DECODER, AUDIO_DECODER_ERROR, createRenderer(new AudioDecoderException("audio-decoder-exception"))},
            new Object[]{RENDERER_DECODER, INITIALISATION_ERROR, createRenderer(new MediaCodecRenderer.DecoderInitializationException(Format.createSampleFormat("id", "sample-mimety[e", 0), new Throwable(), true, 0))},
            new Object[]{RENDERER_DECODER, DECODING_SUBTITLE_ERROR, createRenderer(new SubtitleDecoderException("metadata-decoder-exception"))},

            new Object[]{DRM, UNSUPPORTED_DRM_SCHEME_ERROR, createRenderer(new UnsupportedDrmException(UnsupportedDrmException.REASON_UNSUPPORTED_SCHEME))},
            new Object[]{DRM, DRM_INSTANTIATION_ERROR, createRenderer(new UnsupportedDrmException(UnsupportedDrmException.REASON_INSTANTIATION_ERROR))},
            new Object[]{DRM, DRM_SESSION_ERROR, createRenderer(new DrmSession.DrmSessionException(new Throwable()))},
            new Object[]{DRM, DRM_KEYS_EXPIRED_ERROR, createRenderer(new KeysExpiredException())},
            new Object[]{DRM, MEDIA_REQUIRES_DRM_SESSION_MANAGER_ERROR, createRenderer(new IllegalStateException())},

            new Object[]{CONTENT_DECRYPTION, FAIL_DECRYPT_DATA_DUE_NON_PLATFORM_COMPONENT_ERROR, createRenderer(new DecryptionException(0, "decryption-exception"))},

            new Object[]{UNEXPECTED, MULTIPLE_RENDERER_MEDIA_CLOCK_ENABLED_ERROR, ExoPlaybackExceptionFactory.createForUnexpected(new IllegalStateException("Multiple renderer media clocks enabled."))},
            new Object[]{PlayerErrorType.UNKNOWN, DetailErrorType.UNKNOWN, ExoPlaybackExceptionFactory.createForUnexpected(new IllegalStateException("Any other exception"))}
            // DefaultAudioSink.InvalidAudioTrackTimestampException is private, cannot create
            // EGLSurfaceTexture.GlException is private, cannot create
            // PlaylistStuckException constructor is private, cannot create
            // PlaylistResetException constructor is private, cannot create
            // MediaCodecUtil.DecoderQueryException constructor is private, cannot create
            // DefaultDrmSessionManager.MissingSchemeDataException constructor is private, cannot create
            // Crypto Exceptions cannot be instantiated, it throws a RuntimeException("Stub!")
    );
}
 

@Override
public void onCreate() {
    super.onCreate();

    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
        @SuppressLint("WrongConstant") NotificationChannel notificationChannel = new NotificationChannel(NOTIFICATION_DEFAULT_CHANNEL_ID, getString(R.string.notification_channel_name), NotificationManagerCompat.IMPORTANCE_DEFAULT);
        NotificationManager notificationManager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
        notificationManager.createNotificationChannel(notificationChannel);

        AudioAttributes audioAttributes = new AudioAttributes.Builder()
                .setUsage(AudioAttributes.USAGE_MEDIA)
                .setContentType(AudioAttributes.CONTENT_TYPE_MUSIC)
                .build();
        audioFocusRequest = new AudioFocusRequest.Builder(AudioManager.AUDIOFOCUS_GAIN)
                .setOnAudioFocusChangeListener(audioFocusChangeListener)
                .setAcceptsDelayedFocusGain(false)
                .setWillPauseWhenDucked(true)
                .setAudioAttributes(audioAttributes)
                .build();
    }

    audioManager = (AudioManager) getSystemService(Context.AUDIO_SERVICE);

    mediaSession = new MediaSessionCompat(this, "PlayerService");
    mediaSession.setFlags(MediaSessionCompat.FLAG_HANDLES_MEDIA_BUTTONS | MediaSessionCompat.FLAG_HANDLES_TRANSPORT_CONTROLS);
    mediaSession.setCallback(mediaSessionCallback);

    Context appContext = getApplicationContext();

    Intent activityIntent = new Intent(appContext, MainActivity.class);
    mediaSession.setSessionActivity(PendingIntent.getActivity(appContext, 0, activityIntent, 0));

    Intent mediaButtonIntent = new Intent(Intent.ACTION_MEDIA_BUTTON, null, appContext, MediaButtonReceiver.class);
    mediaSession.setMediaButtonReceiver(PendingIntent.getBroadcast(appContext, 0, mediaButtonIntent, 0));

    exoPlayer = ExoPlayerFactory.newSimpleInstance(this, new DefaultRenderersFactory(this), new DefaultTrackSelector(), new DefaultLoadControl());
    exoPlayer.addListener(exoPlayerListener);
    DataSource.Factory httpDataSourceFactory = new OkHttpDataSourceFactory(new OkHttpClient(), Util.getUserAgent(this, getString(R.string.app_name)));
    Cache cache = new SimpleCache(new File(this.getCacheDir().getAbsolutePath() + "/exoplayer"), new LeastRecentlyUsedCacheEvictor(1024 * 1024 * 100)); // 100 Mb max
    this.dataSourceFactory = new CacheDataSourceFactory(cache, httpDataSourceFactory, CacheDataSource.FLAG_BLOCK_ON_CACHE | CacheDataSource.FLAG_IGNORE_CACHE_ON_ERROR);
    this.extractorsFactory = new DefaultExtractorsFactory();
}
 

public void setCache(Cache cache) {
    this.mCache = cache;
}
 

private Cache newCache() {
    return new SimpleCache(
            new File(mAppContext.getExternalCacheDir(), "exo-video-cache"),//缓存目录
            new LeastRecentlyUsedCacheEvictor(512 * 1024 * 1024),//缓存大小，默认512M，使用LRU算法实现
            new ExoDatabaseProvider(mAppContext));
}
 

/** Returns the {@link Cache} instance. */
public Cache getCache() {
  return cache;
}
 

/** Returns the {@link Cache} instance. */
public Cache getCache() {
  return cache;
}
 

/** Returns the {@link Cache} instance. */
public Cache getCache() {
  return cache;
}
 

/**
 * Constructs a {@link DownloadManager}.
 *
 * @param context Any context.
 * @param databaseProvider Provides the SQLite database in which downloads are persisted.
 * @param cache A cache to be used to store downloaded data. The cache should be configured with
 *     an {@link CacheEvictor} that will not evict downloaded content, for example {@link
 *     NoOpCacheEvictor}.
 * @param upstreamFactory A {@link Factory} for creating {@link DataSource}s for downloading data.
 */
public DownloadManager(
    Context context, DatabaseProvider databaseProvider, Cache cache, Factory upstreamFactory) {
  this(
      context,
      new DefaultDownloadIndex(databaseProvider),
      new DefaultDownloaderFactory(new DownloaderConstructorHelper(cache, upstreamFactory)));
}
 

/**
 * Constructs a {@link DownloadManager}.
 *
 * @param context Any context.
 * @param databaseProvider Provides the SQLite database in which downloads are persisted.
 * @param cache A cache to be used to store downloaded data. The cache should be configured with
 *     an {@link CacheEvictor} that will not evict downloaded content, for example {@link
 *     NoOpCacheEvictor}.
 * @param upstreamFactory A {@link Factory} for creating {@link DataSource}s for downloading data.
 */
public DownloadManager(
    Context context, DatabaseProvider databaseProvider, Cache cache, Factory upstreamFactory) {
  this(
      context,
      new DefaultDownloadIndex(databaseProvider),
      new DefaultDownloaderFactory(new DownloaderConstructorHelper(cache, upstreamFactory)));
}
 

/**
 * Constructs a {@link DownloadManager}.
 *
 * @param context Any context.
 * @param databaseProvider Provides the SQLite database in which downloads are persisted.
 * @param cache A cache to be used to store downloaded data. The cache should be configured with
 *     an {@link CacheEvictor} that will not evict downloaded content, for example {@link
 *     NoOpCacheEvictor}.
 * @param upstreamFactory A {@link Factory} for creating {@link DataSource}s for downloading data.
 */
public DownloadManager(
    Context context, DatabaseProvider databaseProvider, Cache cache, Factory upstreamFactory) {
  this(
      context,
      new DefaultDownloadIndex(databaseProvider),
      new DefaultDownloaderFactory(new DownloaderConstructorHelper(cache, upstreamFactory)));
}
 

/**
 * @param cache Cache instance to be used to store downloaded data.
 * @param upstreamDataSourceFactory A {@link Factory} for downloading data.
 */
public DownloaderConstructorHelper(Cache cache, Factory upstreamDataSourceFactory) {
  this(cache, upstreamDataSourceFactory, null, null, null);
}
 

/**
 * Creates/retrieves the {@link com.google.android.exoplayer2.ExoPlayer} {@link Cache} of the default
 * size {@link #DEFAULT_CACHE_SIZE}.
 *
 * @param context the context
 * @return the {@link com.google.android.exoplayer2.ExoPlayer} {@link Cache}
 */
public static synchronized Cache getCache(@NonNull Context context) {
    return getCache(context, DEFAULT_CACHE_SIZE);
}
 

/**
 * @param cache Cache instance to be used to store downloaded data.
 * @param upstreamDataSourceFactory A {@link Factory} for downloading data.
 */
public DownloaderConstructorHelper(Cache cache, Factory upstreamDataSourceFactory) {
  this(cache, upstreamDataSourceFactory, null, null, null);
}