BasePreloadManager

Artifact: androidx.media3:media3-exoplayer

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Kotlin |Java

@UnstableApi
public abstract class BasePreloadManager<T>

Known direct subclasses

DefaultPreloadManager

DefaultPreloadManager

A preload manager that preloads with the PreloadMediaSource to load the media data into the SampleQueue.

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A base implementation of a preload manager, which maintains the lifecycle of media sources.

Methods should be called on the same thread.

Summary

Nested types
protected abstract class BasePreloadManager.BuilderBase<T> A base class of the builder of the concrete extension of BasePreloadManager.
public interface BasePreloadManager.Listener Listener for events in a preload manager.

Protected fields
final Comparator<T>	rankingDataComparator

Protected constructors
BasePreloadManager(     Comparator<T> rankingDataComparator,     TargetPreloadStatusControl<T> targetPreloadStatusControl,     MediaSource.Factory mediaSourceFactory )

Public methods
final void	add(MediaItem mediaItem, T rankingData) Adds a MediaItem with its rankingData to the preload manager.
final void	add(MediaSource mediaSource, T rankingData) Adds a MediaSource with its rankingData to the preload manager.
void	addListener(BasePreloadManager.Listener listener) Adds a Listener to listen to the preload events.
void	clearListeners() Clears all the listeners.
final @Nullable MediaSource	getMediaSource(MediaItem mediaItem) Returns the MediaSource for the given MediaItem.
final int	getSourceCount() Gets the count of the media sources currently being managed by the preload manager.
final void	invalidate() Invalidates the current preload progress, and triggers a new preload progress based on the new priorities of the managed media sources.
final void	release() Releases the preload manager.
final boolean	remove(MediaItem mediaItem) Removes a MediaItem from the preload manager.
final boolean	remove(MediaSource mediaSource) Removes a MediaSource from the preload manager.
void	removeListener(BasePreloadManager.Listener listener) Removes a Listener.
final void	reset() Resets the preload manager.

Protected methods
abstract void	clearSourceInternal(MediaSource mediaSource) Clears the preloaded data of the given MediaSource, while not releasing the instance of it.
MediaSource	createMediaSourceForPreloading(MediaSource mediaSource) Returns the MediaSource that the preload manager creates for preloading based on the given source.
final @Nullable TargetPreloadStatusControl.PreloadStatus	getTargetPreloadStatus(MediaSource source) Returns the target preload status of the given MediaSource.
final void	onPreloadCompleted(MediaSource source) Called when the given MediaSource completes preloading.
final void	onPreloadError(PreloadException error, MediaSource source) Called when an error occurs.
final void	onPreloadSkipped(MediaSource source) Called when the given MediaSource has been skipped before completing preloading.
abstract void	preloadSourceInternal(MediaSource mediaSource, long startPositionsUs) Preloads the given MediaSource.
void	releaseInternal() Releases the preload manager, see release.
abstract void	releaseSourceInternal(MediaSource mediaSource) Releases the given MediaSource.
boolean	shouldStartPreloadingNextSource() Returns whether the next MediaSource should start preloading.

Protected fields

rankingDataComparator

protected final Comparator<T> rankingDataComparator

Protected constructors

BasePreloadManager

protected BasePreloadManager(
    Comparator<T> rankingDataComparator,
    TargetPreloadStatusControl<T> targetPreloadStatusControl,
    MediaSource.Factory mediaSourceFactory
)

Public methods

add

public final void add(MediaItem mediaItem, T rankingData)

Adds a MediaItem with its rankingData to the preload manager.

Parameters
MediaItem mediaItem	The MediaItem to add.
T rankingData	The ranking data that is associated with the mediaItem.

add

public final void add(MediaSource mediaSource, T rankingData)

Adds a MediaSource with its rankingData to the preload manager.

Parameters
MediaSource mediaSource	The MediaSource to add.
T rankingData	The ranking data that is associated with the mediaSource.

addListener

public void addListener(BasePreloadManager.Listener listener)

Adds a Listener to listen to the preload events.

This method can be called from any thread.

clearListeners

public void clearListeners()

Clears all the listeners.

Throws
java.lang.IllegalStateException	If this method is called from the wrong thread.

getMediaSource

public final @Nullable MediaSource getMediaSource(MediaItem mediaItem)

Returns the MediaSource for the given MediaItem.

Parameters
MediaItem mediaItem	The media item.

Returns
@Nullable MediaSource	The source for the given mediaItem if it is managed by the preload manager, null otherwise.

getSourceCount

public final int getSourceCount()

Gets the count of the media sources currently being managed by the preload manager.

Returns
int	The count of the media sources.

invalidate

public final void invalidate()

Invalidates the current preload progress, and triggers a new preload progress based on the new priorities of the managed media sources.

release

public final void release()

Releases the preload manager.

The preload manager must not be used after calling this method.

remove

public final boolean remove(MediaItem mediaItem)

Removes a MediaItem from the preload manager.

Parameters
MediaItem mediaItem	The MediaItem to remove.

Returns
boolean	true if the preload manager is holding a MediaSource of the given MediaItem and it has been removed, otherwise false.

remove

public final boolean remove(MediaSource mediaSource)

Removes a MediaSource from the preload manager.

Parameters
MediaSource mediaSource	The MediaSource to remove.

Returns
boolean	true if the preload manager is holding the given MediaSource instance and it has been removed, otherwise false.

removeListener

public void removeListener(BasePreloadManager.Listener listener)

Removes a Listener.

Throws
java.lang.IllegalStateException	If this method is called from the wrong thread.

reset

public final void reset()

Resets the preload manager. All sources that the preload manager is holding will be released.

Protected methods

clearSourceInternal

protected abstract void clearSourceInternal(MediaSource mediaSource)

Clears the preloaded data of the given MediaSource, while not releasing the instance of it.

Parameters
MediaSource mediaSource	The media source to clear.

createMediaSourceForPreloading

protected MediaSource createMediaSourceForPreloading(MediaSource mediaSource)

Returns the MediaSource that the preload manager creates for preloading based on the given source. The default implementation returns the same source.

Parameters
MediaSource mediaSource	The source based on which the preload manager creates for preloading.

Returns
MediaSource	The source the preload manager creates for preloading.

getTargetPreloadStatus

protected final @Nullable TargetPreloadStatusControl.PreloadStatus getTargetPreloadStatus(MediaSource source)

Returns the target preload status of the given MediaSource.

onPreloadCompleted

protected final void onPreloadCompleted(MediaSource source)

Called when the given MediaSource completes preloading.

onPreloadError

protected final void onPreloadError(PreloadException error, MediaSource source)

Called when an error occurs.

onPreloadSkipped

protected final void onPreloadSkipped(MediaSource source)

Called when the given MediaSource has been skipped before completing preloading.

preloadSourceInternal

protected abstract void preloadSourceInternal(MediaSource mediaSource, long startPositionsUs)

Preloads the given MediaSource.

Parameters
MediaSource mediaSource	The media source to preload.
long startPositionsUs	The expected starting position in microseconds, or TIME_UNSET to indicate the default start position.

releaseInternal

protected void releaseInternal()

Releases the preload manager, see release.

releaseSourceInternal

protected abstract void releaseSourceInternal(MediaSource mediaSource)

Releases the given MediaSource.

Parameters
MediaSource mediaSource	The media source to release.

shouldStartPreloadingNextSource

protected boolean shouldStartPreloadingNextSource()

Returns whether the next MediaSource should start preloading.