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CallbackDataSource2

public abstract class CallbackDataSource2
extends Object implements Closeable

java.lang.Object
   ↳ androidx.media2.CallbackDataSource2


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 CallbackDataSource2 are visible to future calls. This means you don't need to do your own synchronization unless you're modifying the CallbackDataSource2 from another thread while it's being used by the media library.

Summary

Public constructors

CallbackDataSource2()

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

CallbackDataSource2

public CallbackDataSource2 ()

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 data source 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 there was an error.

Throws
IOException on fatal errors.