Class AdaptiveBufferSizePredictor

  • All Implemented Interfaces:
    BufferSizePredictor

    public class AdaptiveBufferSizePredictor
    extends Object
    implements BufferSizePredictor
    The BufferSizePredictor that automatically increases and decreases the predicted buffer size on feed back.

    It gradually increases the expected number of bytes if the previous buffer fully filled the allocated buffer. It gradually decreases the expected number of 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. TODO: Object type hints could be useful at giving more type-specific predictions

    Since:
    5.0
    Author:
    Trustin Lee, Galder ZamarreƱo
    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      int nextSize​(Object obj)
      Provide the next buffer size taking in account the object to store in the buffer.
      void recordSize​(int previousSize)
      Record the size of the of data in the last buffer used.
    • Constructor Detail

      • AdaptiveBufferSizePredictor

        public AdaptiveBufferSizePredictor()
        Creates a new predictor with the default parameters. With the default parameters, the expected buffer size starts from 512, does not go down below 16, and does not go up above 65536.
      • AdaptiveBufferSizePredictor

        public AdaptiveBufferSizePredictor​(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

      • nextSize

        public int nextSize​(Object obj)
        Description copied from interface: BufferSizePredictor
        Provide the next buffer size taking in account the object to store in the buffer.
        Specified by:
        nextSize in interface BufferSizePredictor
        Parameters:
        obj - instance that will be stored in the buffer
        Returns:
        int representing the next predicted buffer size
      • recordSize

        public void recordSize​(int previousSize)
        Description copied from interface: BufferSizePredictor
        Record the size of the of data in the last buffer used.
        Specified by:
        recordSize in interface BufferSizePredictor
        Parameters:
        previousSize - int representing the size of the last object buffered.