io.netty.handler.codec.http2

Interface Http2LocalFlowController

All Superinterfaces:

Http2FlowController

All Known Implementing Classes:

DefaultHttp2LocalFlowController

@UnstableApi
public interface Http2LocalFlowController
extends Http2FlowController

A Http2FlowController for controlling the inbound flow of DATA frames from the remote endpoint.

Method Summary

Modifier and Type	Method and Description
boolean	consumeBytes(Http2Stream stream, int numBytes) Indicates that the application has consumed a number of bytes for the given stream and is therefore ready to receive more data from the remote endpoint.
Http2LocalFlowController	frameWriter(Http2FrameWriter frameWriter) Sets the writer to be use for sending WINDOW_UPDATE frames.
int	initialWindowSize(Http2Stream stream) Get the initial flow control window size for the given stream.
void	receiveFlowControlledFrame(Http2Stream stream, ByteBuf data, int padding, boolean endOfStream) Receives an inbound DATA frame from the remote endpoint and applies flow control policies to it for both the stream as well as the connection.
int	unconsumedBytes(Http2Stream stream) The number of bytes for the given stream that have been received but not yet consumed by the application.

Methods inherited from interface io.netty.handler.codec.http2.Http2FlowController

channelHandlerContext, incrementWindowSize, initialWindowSize, initialWindowSize, windowSize

Method Detail

frameWriter

Http2LocalFlowController frameWriter(Http2FrameWriter frameWriter)

Sets the writer to be use for sending WINDOW_UPDATE frames. This must be called before any flow controlled data is received.

Parameters:

frameWriter - the HTTP/2 frame writer.

receiveFlowControlledFrame

void receiveFlowControlledFrame(Http2Stream stream,
                                ByteBuf data,
                                int padding,
                                boolean endOfStream)
                         throws Http2Exception

Receives an inbound DATA frame from the remote endpoint and applies flow control policies to it for both the stream as well as the connection. If any flow control policies have been violated, an exception is raised immediately, otherwise the frame is considered to have "passed" flow control.

If stream is null or closed, flow control should only be applied to the connection window and the bytes are immediately consumed.

Parameters:

stream - the subject stream for the received frame. The connection stream object must not be used. If stream is null or closed, flow control should only be applied to the connection window and the bytes are immediately consumed.

data - payload buffer for the frame.

padding - additional bytes that should be added to obscure the true content size. Must be between 0 and 256 (inclusive).

endOfStream - Indicates whether this is the last frame to be sent from the remote endpoint for this stream.

Throws:

Http2Exception - if any flow control errors are encountered.

consumeBytes

boolean consumeBytes(Http2Stream stream,
                     int numBytes)
              throws Http2Exception

Indicates that the application has consumed a number of bytes for the given stream and is therefore ready to receive more data from the remote endpoint. The application must consume any bytes that it receives or the flow control window will collapse. Consuming bytes enables the flow controller to send WINDOW_UPDATE to restore a portion of the flow control window for the stream.

If stream is null or closed (i.e. Http2Stream.state() method returns Http2Stream.State.CLOSED), calling this method has no effect.

Parameters:

stream - the stream for which window space should be freed. The connection stream object must not be used. If stream is null or closed (i.e. Http2Stream.state() method returns Http2Stream.State.CLOSED), calling this method has no effect.

numBytes - the number of bytes to be returned to the flow control window.

Returns:

true if a WINDOW_UPDATE was sent, false otherwise.

Throws:

Http2Exception - if the number of bytes returned exceeds the unconsumedBytes(Http2Stream) for the stream.

unconsumedBytes

int unconsumedBytes(Http2Stream stream)

The number of bytes for the given stream that have been received but not yet consumed by the application.

Parameters:

stream - the stream for which window space should be freed.

Returns:

the number of unconsumed bytes for the stream.

initialWindowSize

int initialWindowSize(Http2Stream stream)

Get the initial flow control window size for the given stream. This quantity is measured in number of bytes. Note the unavailable window portion can be calculated by Http2FlowController.initialWindowSize() - Http2FlowController.windowSize(Http2Stream).