Interface StreamByteDistributor

All Known Implementing Classes:

UniformStreamByteDistributor, WeightedFairQueueByteDistributor

public interface StreamByteDistributor

An object (used by remote flow control) that is responsible for distributing the bytes to be written across the streams in the connection.

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static interface	StreamByteDistributor.StreamState	State information for the stream, indicating the number of bytes that are currently streamable.
static interface	StreamByteDistributor.Writer	Object that performs the writing of the bytes that have been allocated for a stream.

Method Summary

Modifier and Type	Method	Description
boolean	distribute(int maxBytes, StreamByteDistributor.Writer writer)	Distributes up to maxBytes to those streams containing streamable bytes and iterates across those streams to write the appropriate bytes.
void	updateDependencyTree(int childStreamId, int parentStreamId, short weight, boolean exclusive)	Explicitly update the dependency tree.
void	updateStreamableBytes(StreamByteDistributor.StreamState state)	Called when the streamable bytes for a stream has changed.

Method Details

updateStreamableBytes

void updateStreamableBytes(StreamByteDistributor.StreamState state)

Called when the streamable bytes for a stream has changed. Until this method is called for the first time for a give stream, the stream is assumed to have no streamable bytes.

updateDependencyTree

void updateDependencyTree(int childStreamId,
 int parentStreamId,
 short weight,
 boolean exclusive)

Explicitly update the dependency tree. This method is called independently of stream state changes.

Parameters:

childStreamId - The stream identifier associated with the child stream.

parentStreamId - The stream identifier associated with the parent stream. May be 0, to make childStreamId and immediate child of the connection.

weight - The weight which is used relative to other child streams for parentStreamId. This value must be between 1 and 256 (inclusive).

exclusive - If childStreamId should be the exclusive dependency of parentStreamId.

distribute

boolean distribute(int maxBytes,
 StreamByteDistributor.Writer writer)
            throws Http2Exception

Distributes up to maxBytes to those streams containing streamable bytes and iterates across those streams to write the appropriate bytes. Criteria for traversing streams is undefined and it is up to the implementation to determine when to stop at a given stream.

The streamable bytes are not automatically updated by calling this method. It is up to the caller to indicate the number of bytes streamable after the write by calling updateStreamableBytes(StreamState).

Parameters:

maxBytes - the maximum number of bytes to write.

Returns:

true if there are still streamable bytes that have not yet been written, otherwise false.

Throws:

Http2Exception - If an internal exception occurs and internal connection state would otherwise be corrupted.