com.google.android.exoplayer2.source

Interface MediaPeriod

All Superinterfaces:

SequenceableLoader

All Known Implementing Classes:

ClippingMediaPeriod

public interface MediaPeriod
extends SequenceableLoader

A source of a single period of media.

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static interface	MediaPeriod.Callback A callback to be notified of MediaPeriod events.

Method Summary

Modifier and Type	Method and Description
boolean	continueLoading(long positionUs) Attempts to continue loading.
void	discardBuffer(long positionUs) Discards buffered media up to the specified position.
long	getBufferedPositionUs() Returns an estimate of the position up to which data is buffered for the enabled tracks.
long	getNextLoadPositionUs() Returns the next load time, or C.TIME_END_OF_SOURCE if loading has finished.
TrackGroupArray	getTrackGroups() Returns the TrackGroups exposed by the period.
void	maybeThrowPrepareError() Throws an error that's preventing the period from becoming prepared.
void	prepare(MediaPeriod.Callback callback) Prepares this media period asynchronously.
long	readDiscontinuity() Attempts to read a discontinuity.
long	seekToUs(long positionUs) Attempts to seek to the specified position in microseconds.
long	selectTracks(TrackSelection[] selections, boolean[] mayRetainStreamFlags, SampleStream[] streams, boolean[] streamResetFlags, long positionUs) Performs a track selection.

Method Detail

prepare

void prepare(MediaPeriod.Callback callback)

Prepares this media period asynchronously.

callback.onPrepared is called when preparation completes. If preparation fails, maybeThrowPrepareError() will throw an IOException.

If preparation succeeds and results in a source timeline change (e.g. the period duration becoming known), MediaSource.Listener.onSourceInfoRefreshed(Timeline, Object) will be called before callback.onPrepared.

Parameters:

callback - Callback to receive updates from this period, including being notified when preparation completes.

maybeThrowPrepareError

void maybeThrowPrepareError()
                     throws java.io.IOException

Throws an error that's preventing the period from becoming prepared. Does nothing if no such error exists.

This method should only be called before the period has completed preparation.

Throws:

java.io.IOException - The underlying error.

getTrackGroups

TrackGroupArray getTrackGroups()

Returns the TrackGroups exposed by the period.

This method should only be called after the period has been prepared.

Returns:

The TrackGroups.

selectTracks

long selectTracks(TrackSelection[] selections,
                  boolean[] mayRetainStreamFlags,
                  SampleStream[] streams,
                  boolean[] streamResetFlags,
                  long positionUs)

Performs a track selection.

The call receives track selections for each renderer, mayRetainStreamFlags indicating whether the existing SampleStream can be retained for each selection, and the existing streams themselves. The call will update streams to reflect the provided selections, clearing, setting and replacing entries as required. If an existing sample stream is retained but with the requirement that the consuming renderer be reset, then the corresponding flag in streamResetFlags will be set to true. This flag will also be set if a new sample stream is created.

This method should only be called after the period has been prepared.

Parameters:

selections - The renderer track selections.

mayRetainStreamFlags - Flags indicating whether the existing sample stream can be retained for each selection. A true value indicates that the selection is unchanged, and that the caller does not require that the sample stream be recreated.

streams - The existing sample streams, which will be updated to reflect the provided selections.

streamResetFlags - Will be updated to indicate new sample streams, and sample streams that have been retained but with the requirement that the consuming renderer be reset.

positionUs - The current playback position in microseconds.

Returns:

The actual position at which the tracks were enabled, in microseconds.

discardBuffer

void discardBuffer(long positionUs)

Discards buffered media up to the specified position.

Parameters:

positionUs - The position in microseconds.

readDiscontinuity

long readDiscontinuity()

Attempts to read a discontinuity.

After this method has returned a value other than C.TIME_UNSET, all SampleStreams provided by the period are guaranteed to start from a key frame.

Returns:

If a discontinuity was read then the playback position in microseconds after the discontinuity. Else C.TIME_UNSET.

getBufferedPositionUs

long getBufferedPositionUs()

Returns an estimate of the position up to which data is buffered for the enabled tracks.

This method should only be called when at least one track is selected.

Returns:

An estimate of the absolute position in microseconds up to which data is buffered, or C.TIME_END_OF_SOURCE if the track is fully buffered.

seekToUs

long seekToUs(long positionUs)

Attempts to seek to the specified position in microseconds.

After this method has been called, all SampleStreams provided by the period are guaranteed to start from a key frame.

This method should only be called when at least one track is selected.

Parameters:

positionUs - The seek position in microseconds.

Returns:

The actual position to which the period was seeked, in microseconds.

getNextLoadPositionUs

long getNextLoadPositionUs()

Returns the next load time, or C.TIME_END_OF_SOURCE if loading has finished.

This method should only be called after the period has been prepared. It may be called when no tracks are selected.

Specified by:

getNextLoadPositionUs in interface SequenceableLoader

continueLoading

boolean continueLoading(long positionUs)

Attempts to continue loading.

This method may be called both during and after the period has been prepared.

A period may call SequenceableLoader.Callback.onContinueLoadingRequested(SequenceableLoader) on the MediaPeriod.Callback passed to prepare(Callback) to request that this method be called when the period is permitted to continue loading data. A period may do this both during and after preparation.

Specified by:

continueLoading in interface SequenceableLoader

Parameters:

positionUs - The current playback position.

Returns:

True if progress was made, meaning that getNextLoadPositionUs() will return a different value than prior to the call. False otherwise.