org.jboss.netty.channel
Class AdaptiveReceiveBufferSizePredictor

java.lang.Object
  org.jboss.netty.channel.AdaptiveReceiveBufferSizePredictor

All Implemented Interfaces:

ReceiveBufferSizePredictor

public class AdaptiveReceiveBufferSizePredictor
extends Object
implements ReceiveBufferSizePredictor

The ReceiveBufferSizePredictor that automatically increases and decreases the predicted buffer size on feed back.

It gradually increases the expected number of readable bytes if the previous read fully filled the allocated buffer. It gradually decreases the expected number of readable bytes if the read operation was not able to fill a certain amount of the allocated buffer two times consecutively. Otherwise, it keeps returning the same prediction.

Version:

$Rev: 2080 $, $Date: 2010-01-26 18:04:19 +0900 (Tue, 26 Jan 2010) $

Author:

The Netty Project, Trustin Lee

Constructor Summary

AdaptiveReceiveBufferSizePredictor()
Creates a new predictor with the default parameters.

AdaptiveReceiveBufferSizePredictor(int minimum, int initial, int maximum)
Creates a new predictor with the specified parameters.

Method Summary

int	nextReceiveBufferSize() Predicts the capacity of the ChannelBuffer for the next read operation depending on the actual number of read bytes in the previous read operation.
void	previousReceiveBufferSize(int previousReceiveBufferSize) Updates this predictor by specifying the actual number of read bytes in the previous read operation.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

AdaptiveReceiveBufferSizePredictor

public AdaptiveReceiveBufferSizePredictor()

Creates a new predictor with the default parameters. With the default parameters, the expected buffer size starts from 1024, does not go down below 64, and does not go up above 65536.

AdaptiveReceiveBufferSizePredictor

public AdaptiveReceiveBufferSizePredictor(int minimum,
                                          int initial,
                                          int maximum)

Creates a new predictor with the specified parameters.

Parameters:

minimum - the inclusive lower bound of the expected buffer size

initial - the initial buffer size when no feed back was received

maximum - the inclusive upper bound of the expected buffer size

Method Detail

nextReceiveBufferSize

public int nextReceiveBufferSize()

Description copied from interface: ReceiveBufferSizePredictor

Predicts the capacity of the ChannelBuffer for the next read operation depending on the actual number of read bytes in the previous read operation.

Specified by:

nextReceiveBufferSize in interface ReceiveBufferSizePredictor

Returns:

the expected number of readable bytes this time

previousReceiveBufferSize

public void previousReceiveBufferSize(int previousReceiveBufferSize)

Description copied from interface: ReceiveBufferSizePredictor

Updates this predictor by specifying the actual number of read bytes in the previous read operation.

Specified by:

previousReceiveBufferSize in interface ReceiveBufferSizePredictor

Parameters:

previousReceiveBufferSize - the actual number of read bytes in the previous read operation