org.openimaj.util.hash

Class StringMurmurHashFunction

java.lang.Object

org.openimaj.util.hash.StringMurmurHashFunction

All Implemented Interfaces:

HashFunction<String>

public class StringMurmurHashFunction
extends Object
implements HashFunction<String>

Use MurmurHash (http://murmurhash.googlepages.com/) to generate a random hash for a string.

Author:

Sina Samangooei (ss@ecs.soton.ac.uk)

Constructor Summary

Constructors

Constructor and Description
StringMurmurHashFunction() Construct a new StringMurmurHashFunction with the default seed.
StringMurmurHashFunction(int seed) Construct a new StringMurmurHashFunction with the given seed.

Method Summary

Modifier and Type	Method and Description
int	computeHashCode(String data) Compute the hash code for the object
static int	murmurhash(byte[] data) Compute the Murmur hash (http://murmurhash.googlepages.com/) of the given bytes.
static int	murmurhash(byte[] data, int seed) Compute the Murmur hash (http://murmurhash.googlepages.com/) of the given bytes.
static int	murmurhash(byte[] data, int length, int seed) Compute the Murmur hash (http://murmurhash.googlepages.com/) of the given bytes.

Methods inherited from class java.lang.Object

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

Constructor Detail

StringMurmurHashFunction

public StringMurmurHashFunction()

Construct a new StringMurmurHashFunction with the default seed.

StringMurmurHashFunction

public StringMurmurHashFunction(int seed)

Construct a new StringMurmurHashFunction with the given seed.

Parameters:

seed - the seed

Method Detail

computeHashCode

public int computeHashCode(String data)

Description copied from interface: HashFunction

Compute the hash code for the object

Specified by:

computeHashCode in interface HashFunction<String>

Parameters:

data - the object

Returns:

the hash code

murmurhash

public static int murmurhash(byte[] data)

Compute the Murmur hash (http://murmurhash.googlepages.com/) of the given bytes.

Parameters:

data - the data to hash

Returns:

the murmur hash

See Also:

murmurhash(byte[], int, int)

murmurhash

public static int murmurhash(byte[] data,
                             int seed)

Compute the Murmur hash (http://murmurhash.googlepages.com/) of the given bytes.

Parameters:

data - the data to hash

seed - the random seed

Returns:

the murmur hash

See Also:

murmurhash(byte[], int, int)

murmurhash

public static int murmurhash(byte[] data,
                             int length,
                             int seed)

Compute the Murmur hash (http://murmurhash.googlepages.com/) of the given bytes. Based on the implementation from https://github.com/clearspring/stream-lib.

Parameters:

data - the data to hash

length - the length of the data to hash

seed - the random seed

Returns:

the murmur hash