it.uniroma3.mat.extendedset.utilities

Class IntHashCode

java.lang.Object

it.uniroma3.mat.extendedset.utilities.IntHashCode

public class IntHashCode
extends Object

Hash functions for integers and integer arrays.

Version:

$Id: IntHashCode.java 127 2010-12-21 20:22:12Z cocciasik $

Author:

Alessandro Colantonio

Constructor Summary

Constructors

Constructor and Description
IntHashCode()

Method Summary

Methods

Modifier and Type	Method and Description
static int	hashCode(int key) Computes a hashcode for an integer
static int	hashCode(int[] keys) Computes the hashcode of an array of integers
static int	hashCode(int[] keys, int len, int seed) Computes the hashcode of an array of integers

Methods inherited from class java.lang.Object

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

Constructor Detail

IntHashCode

public IntHashCode()

Method Detail

hashCode

public static int hashCode(int key)

Computes a hashcode for an integer

Inspired by Thomas Wang's function, described at http://www.concentric.net/~ttwang/tech/inthash.htm

Parameters:

key - the given integer

Returns:

the hashcode

hashCode

public static int hashCode(int[] keys)

Computes the hashcode of an array of integers

Parameters:

keys - the given integer array

Returns:

the hashcode

hashCode

public static int hashCode(int[] keys,
           int len,
           int seed)

Computes the hashcode of an array of integers

It is based on MurmurHash3 Algorithm, described at http://sites.google.com/site/murmurhash

Parameters:

keys - the given integer array

len - number of elements to include, that is len <= keys.length

seed - initial seed

Returns:

the hashcode