org.egothor.duplicity.util

Class Permutations

java.lang.Object

org.egothor.duplicity.util.Permutations

public class Permutations
extends Object

Creates random permutations. The length of permutation is determined during the class instantiation.

Author:

Kateřina Dufková

Constructor Summary

Constructors

Constructor and Description
Permutations(int length) Creates instance with random seed.
Permutations(int length, long seed) Creates instance with given seed.

Method Summary

Modifier and Type	Method and Description
int	getLength()
long	getSeed()
Permutation	randomPermutation() Generates random permutation of integers [0 ..

Methods inherited from class java.lang.Object

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

Constructor Detail

Permutations

public Permutations(int length)

Creates instance with random seed.

Parameters:

length - length of permutations to be created by this instance

Permutations

public Permutations(int length,
                    long seed)

Creates instance with given seed.

Parameters:

length - length of permutations to be created by this instance

seed - seed to be used

Method Detail

getLength

public int getLength()

getSeed

public long getSeed()

randomPermutation

public Permutation randomPermutation()

Generates random permutation of integers [0 .. getLength()-1]. The method uses Knuth algorithm.

Returns:

new random permutation object

See Also:

Wikipedia