org.jamesframework.ext.permutation

Class PermutationSolution

java.lang.Object

org.jamesframework.core.problems.Solution

org.jamesframework.ext.permutation.PermutationSolution

public class PermutationSolution
extends org.jamesframework.core.problems.Solution

High-level order solution modeled in terms of IDs of ordered items. The order consists of an ordered sequence of items which are each assumed to be identified using a unique integer ID.

Author:

Herman De Beukelaer

Constructor Summary

Constructors

Constructor and Description
PermutationSolution(List<Integer> order) Creates a order solution.

Method Summary

Modifier and Type	Method and Description
PermutationSolution	copy() Creates a deep copy of this permutation solution with the same order of IDs.
boolean	equals(Object other) Checks whether the given other object is also a permutation solution consisting of the same IDs in exactly the same order.
List<Integer>	getOrder() Get an unmodifiable view of the current order of IDs.
int	hashCode() Hash code computation corresponding to the implementation of equals(Object).
int	size() Get the number of items in this permutation.
void	swap(int i, int j) Swap the items at position i and j in the permutation.

Methods inherited from class org.jamesframework.core.problems.Solution

checkedCopy

Methods inherited from class java.lang.Object

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

Constructor Detail

PermutationSolution

public PermutationSolution(List<Integer> order)

Creates a order solution. Items are ordered according to the given list of IDs. Contents of this list are copied into internal data structures so that no reference to the given list is stored in this solution.

Parameters:

order - ordered IDs

Throws:

IllegalArgumentException - if order is empty or contains duplicates

NullPointerException - if order is null or contains any null elements

Method Detail

getOrder

public List<Integer> getOrder()

Get an unmodifiable view of the current order of IDs.

Returns:

ordered IDs

size

public int size()

Get the number of items in this permutation.

Returns:

size of this permutation

swap

public void swap(int i,
                 int j)

Swap the items at position i and j in the permutation. Both positions should be different, positive (zero included) and less than the number of items in the permutation.

Parameters:

i - position of first item to be swapped

j - position of second item to be swapped

Throws:

org.jamesframework.core.exceptions.SolutionModificationException - if i and j are equal or one of both arguments is negative or larger than or equal to the number of items in the permutation

copy

public PermutationSolution copy()

Creates a deep copy of this permutation solution with the same order of IDs. The copy does not share any object references with the original solution.

Specified by:

copy in class org.jamesframework.core.problems.Solution

Returns:

deep copy

equals

public boolean equals(Object other)

Checks whether the given other object is also a permutation solution consisting of the same IDs in exactly the same order.

Specified by:

equals in class org.jamesframework.core.problems.Solution

Parameters:

other - object to compare for equality

Returns:

true if the given object is an equal permutation solution

hashCode

public int hashCode()

Hash code computation corresponding to the implementation of equals(Object).

Specified by:

hashCode in class org.jamesframework.core.problems.Solution

Returns:

hash code