com.aoindustries.util.sort

Class ShellSort

java.lang.Object

com.aoindustries.util.sort.ShellSort

All Implemented Interfaces:

ComparisonSortAlgorithm<Object>, SortAlgorithm<Object>

public final class ShellSort
extends Object

A shell sort demonstration algorithm SortAlgorithm.java, Thu Oct 27 10:32:35 1994 Note: Invented by Donald Lewis Shell [CACM, July, 1959, pages 30-32]

Version:

1.0, 23 Jun 1995, 1.1, 12 Apr 2000 -- fixed java.lang.ArrayIndexOutOfBoundsException Joel Berry found this bug

http://www.auto.tuwien.ac.at/~blieb/woop/shell.html Shellsort is a simple extension of insertion sort which gains speed by allowing exchanges of elements that are far apart. The idea is to rearrange the array to give it the property that every hth element (starting anywhere) yields a sorted array. Such an array is said to be h-sorted. By h-sorting for some large values of h, we can move elements in the array long distances and thus make it easier to h-sort for smaller values of h. Using such a procedure for any sequence of values h which ends in 1 will produce a sorted array.

Adapted from Jason Harrison's ShellSortAlgorithm.

Author:

Jason Harrison@cs.ubc.ca

Method Summary

Modifier and Type	Method and Description
protected static <T> int	compare(List<T> list, int i, int j, Comparator<? super T> comparator, SortStatistics stats)
protected static <T> int	compare(T[] array, int i, int j, Comparator<? super T> comparator, SortStatistics stats)
protected static <T> int	compare(T O1, T O2, Comparator<? super T> comparator, SortStatistics stats)
protected static <T> T	get(List<T> list, int i, SortStatistics stats)
protected static <T> T	get(T[] array, int i, SortStatistics stats)
static ShellSort	getInstance()
boolean	isStable() Checks if this is a stable sort.
protected static <T> void	set(List<T> list, int i, T O, SortStatistics stats)
protected static <T> void	set(T[] array, int i, T O, SortStatistics stats)
<T extends E> void	sort(List<T> list)
<T extends E> void	sort(List<T> list, Comparator<? super T> comparator)
<T> void	sort(List<T> list, Comparator<? super T> comparator, SortStatistics stats)
<T extends E> void	sort(List<T> list, SortStatistics stats)
<T extends E> void	sort(T[] array)
<T extends E> void	sort(T[] array, Comparator<? super T> comparator)
<T> void	sort(T[] array, Comparator<? super T> comparator, SortStatistics stats)
<T extends E> void	sort(T[] array, SortStatistics stats)
protected static <T> void	swap(List<T> list, int i, int j, SortStatistics stats)
protected static <T> void	swap(T[] array, int i, int j, SortStatistics stats)

Methods inherited from class java.lang.Object

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

Method Detail

getInstance

public static ShellSort getInstance()

isStable

public boolean isStable()

Description copied from interface: SortAlgorithm

Checks if this is a stable sort. A stable sort will keep elements with equal values in their same relative order.

sort

public <T> void sort(List<T> list,
                     Comparator<? super T> comparator,
                     SortStatistics stats)

Specified by:

sort in interface ComparisonSortAlgorithm<Object>

sort

public <T> void sort(T[] array,
                     Comparator<? super T> comparator,
                     SortStatistics stats)

Specified by:

sort in interface ComparisonSortAlgorithm<Object>

sort

public <T extends E> void sort(List<T> list)

Specified by:

sort in interface SortAlgorithm<E>

sort

public <T extends E> void sort(T[] array)

Specified by:

sort in interface SortAlgorithm<E>

sort

public <T extends E> void sort(List<T> list,
                               SortStatistics stats)

Specified by:

sort in interface SortAlgorithm<E>

sort

public <T extends E> void sort(T[] array,
                               SortStatistics stats)

Specified by:

sort in interface SortAlgorithm<E>

sort

public <T extends E> void sort(List<T> list,
                               Comparator<? super T> comparator)

Specified by:

sort in interface ComparisonSortAlgorithm<E>

sort

public <T extends E> void sort(T[] array,
                               Comparator<? super T> comparator)

Specified by:

sort in interface ComparisonSortAlgorithm<E>

compare

protected static <T> int compare(List<T> list,
                                 int i,
                                 int j,
                                 Comparator<? super T> comparator,
                                 SortStatistics stats)

compare

protected static <T> int compare(T[] array,
                                 int i,
                                 int j,
                                 Comparator<? super T> comparator,
                                 SortStatistics stats)

compare

protected static <T> int compare(T O1,
                                 T O2,
                                 Comparator<? super T> comparator,
                                 SortStatistics stats)

get

protected static <T> T get(List<T> list,
                           int i,
                           SortStatistics stats)

get

protected static <T> T get(T[] array,
                           int i,
                           SortStatistics stats)

set

protected static <T> void set(List<T> list,
                              int i,
                              T O,
                              SortStatistics stats)

set

protected static <T> void set(T[] array,
                              int i,
                              T O,
                              SortStatistics stats)

swap

protected static <T> void swap(List<T> list,
                               int i,
                               int j,
                               SortStatistics stats)

swap

protected static <T> void swap(T[] array,
                               int i,
                               int j,
                               SortStatistics stats)