Android Dev Summit, October 23-24: two days of technical content, directly from the Android team. Sign-up for livestream updates.

DataSourceCallback

public abstract class DataSourceCallback
extends Object implements Closeable

java.lang.Object
   ↳ androidx.media2.common.DataSourceCallback


For supplying media data, implement this if your app has special requirements for the way media data is obtained.

Methods of this interface may be called on multiple different threads. There will be a thread synchronization point between each call to ensure that modifications to the state of your DataSourceCallback are visible to future calls. This means you don't need to do your own synchronization unless you're modifying the DataSourceCallback from another thread while it's being used by the media library.

Summary

Public constructors

DataSourceCallback()

Public methods

abstract long getSize()

Called to get the size of the data source.

abstract int readAt(long position, byte[] buffer, int offset, int size)

Called to request data from the given position.

Inherited methods

Public constructors

DataSourceCallback

public DataSourceCallback ()

Public methods

getSize

public abstract long getSize ()

Called to get the size of the data source.

Returns
long the size of data source in bytes, or -1 if the size is unknown.

Throws
IOException on fatal errors

readAt

public abstract int readAt (long position, 
                byte[] buffer, 
                int offset, 
                int size)

Called to request data from the given position. Implementations should should write up to size bytes into buffer, and return the number of bytes written. Return 0 if size is zero (thus no bytes are read). Return -1 to indicate that end of stream is reached.

Parameters
position long: the position in the media item to read from.

buffer byte: the buffer to read the data into.

offset int: the offset within buffer to read the data into.

size int: the number of bytes to read.

Returns
int the number of bytes read, or -1 if the end of stream was reached.

Throws
IOException on fatal errors.