net.sf.zig_project.gpl.common.arrays
Class ExponentialRatioArraySizeSelector

java.lang.Object
  net.sf.zig_project.gpl.common.arrays.ExponentialRatioArraySizeSelector

All Implemented Interfaces:

ArraySizeSelector

public final class ExponentialRatioArraySizeSelector

extends Object

implements ArraySizeSelector

The Exponential Array Sizer recommends an array size. The result is based on a growth ratio, scaled by the current array size. The growth ratio used is an exponential fall off, starting from a high ratio, and moving towards a low ratio. This results in recommended increases that are on a large scale for small arrays (such as those just initialized), and small scales for large arrays (to preserve memory).

Version:

September 15, 2004

Author:

Frank Ziglar

See Also:

ArraySizeSelector.DEFAULT

Field Summary

Fields inherited from interface net.sf.zig_project.gpl.common.arrays.ArraySizeSelector

DEFAULT

Constructor Summary

ExponentialRatioArraySizeSelector(double xpnt, double min, double range)

Method Summary

int	grow(int n, int rm) When an array size is increased, this method will recommend a new size.

Methods inherited from class java.lang.Object

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

Constructor Detail

ExponentialRatioArraySizeSelector

public ExponentialRatioArraySizeSelector(double xpnt,
                                         double min,
                                         double range)

Method Detail

grow

public int grow(int n,
                int rm)

Description copied from interface: ArraySizeSelector

When an array size is increased, this method will recommend a new size. Implementations are required to ensure that the returned value is always >= current_size+extra_room. This value will typically be larger than just the sum however, in order to minimized the number of times the array need be reallocated.

Specified by:

grow in interface ArraySizeSelector

Parameters:

n - the length of the currently allocated array

rm - an estimate of the number of elements that need to be added to the array before the size is reconsidered.

Returns:

the total recommended size for a new array