Package gnu.kawa.util

Class HashUtils

java.lang.Object

gnu.kawa.util.HashUtils

public class HashUtils
extends Object

Various static helper methods for calculating hash-codes. These are designed to tolerate cyclic data structrues, by using a recursive/iteration limit. The actual hash functions used (unless we fall back to Object#hashCode) is the MurmurHash3 algorithm: http://en.wikipedia.org/wiki/MurmurHash https://code.google.com/p/smhasher/wiki/MurmurHash3

Constructor Summary

Constructors

Constructor	Description
HashUtils()

Method Summary

Modifier and Type	Method	Description
static int	boundedHash(Array arr, int seed, int limit)
static int	boundedHash(Object object)
static int	boundedHash(Object object, int seed, int limit)	Generic hash method.
static int	boundedHash(List object, int seed, int limit)
static int	boundedHashArray(Object object, int seed, int limit)
static int	hashInt(int seed, int value)
static int	murmur3finish(int hash, int length)
static int	murmur3step(int h1, int k1)

Methods inherited from class java.lang.Object

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

Constructor Details

HashUtils

public HashUtils()

Method Details

boundedHash

public static int boundedHash(Object object)

boundedHash

public static int boundedHash(Object object,
 int seed,
 int limit)

Generic hash method. See BoundedHashable for a discussion of the parameters.

hashInt

public static int hashInt(int seed,
 int value)

boundedHash

public static int boundedHash(List object,
 int seed,
 int limit)

boundedHashArray

public static int boundedHashArray(Object object,
 int seed,
 int limit)

boundedHash

public static int boundedHash(Array arr,
 int seed,
 int limit)

murmur3step

public static int murmur3step(int h1,
 int k1)

murmur3finish

public static int murmur3finish(int hash,
 int length)