Package org.redisson.misc

Class HighwayHash

java.lang.Object

org.redisson.misc.HighwayHash

public final class HighwayHash
extends Object

HighwayHash algorithm. See HighwayHash on GitHub

Constructor Summary

Constructors

Constructor	Description
HighwayHash(long[] key)
HighwayHash(long key0, long key1, long key2, long key3)

Method Summary

Modifier and Type	Method	Description
long[]	finalize128()	Computes the hash value after all bytes were processed.
long[]	finalize256()	Computes the hash value after all bytes were processed.
long	finalize64()	Computes the hash value after all bytes were processed.
static long[]	hash128(byte[] data, int offset, int length, long[] key)	NOTE: The 128-bit HighwayHash algorithm is not yet frozen and subject to change.
static long[]	hash256(byte[] data, int offset, int length, long[] key)	NOTE: The 256-bit HighwayHash algorithm is not yet frozen and subject to change.
static long	hash64(byte[] data, int offset, int length, long[] key)	NOTE: The 64-bit HighwayHash algorithm is declared stable and no longer subject to change.
void	update(long a0, long a1, long a2, long a3)	Updates the hash with 32 bytes of data given as 4 longs.
void	updatePacket(byte[] packet, int pos)	Updates the hash with 32 bytes of data.
void	updateRemainder(byte[] bytes, int pos, int size_mod32)	Updates the hash with the last 1 to 31 bytes of the data.

Methods inherited from class java.lang.Object

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

Constructor Detail

HighwayHash

public HighwayHash(long key0,
                   long key1,
                   long key2,
                   long key3)

Parameters:

key0 - first 8 bytes of the key

key1 - next 8 bytes of the key

key2 - next 8 bytes of the key

key3 - last 8 bytes of the key

HighwayHash

public HighwayHash(long[] key)

Parameters:

key - array of size 4 with the key to initialize the hash with

Method Detail

updatePacket

public void updatePacket(byte[] packet,
                         int pos)

Updates the hash with 32 bytes of data. If you can read 4 long values from your data efficiently, prefer using update() instead for more speed.

Parameters:

packet - data array which has a length of at least pos + 32

pos - position in the array to read the first of 32 bytes from

update

public void update(long a0,
                   long a1,
                   long a2,
                   long a3)

Updates the hash with 32 bytes of data given as 4 longs. This function is more efficient than updatePacket when you can use it.

Parameters:

a0 - first 8 bytes in little endian 64-bit long

a1 - next 8 bytes in little endian 64-bit long

a2 - next 8 bytes in little endian 64-bit long

a3 - last 8 bytes in little endian 64-bit long

updateRemainder

public void updateRemainder(byte[] bytes,
                            int pos,
                            int size_mod32)

Updates the hash with the last 1 to 31 bytes of the data. You must use updatePacket first per 32 bytes of the data, if and only if 1 to 31 bytes of the data are not processed after that, updateRemainder must be used for those final bytes.

Parameters:

bytes - data array which has a length of at least pos + size_mod32

pos - position in the array to start reading size_mod32 bytes from

size_mod32 - the amount of bytes to read

finalize64

public long finalize64()

Computes the hash value after all bytes were processed. Invalidates the state. NOTE: The 64-bit HighwayHash algorithm is declared stable and no longer subject to change.

Returns:

64-bit hash

finalize128

public long[] finalize128()

Computes the hash value after all bytes were processed. Invalidates the state. NOTE: The 128-bit HighwayHash algorithm is not yet frozen and subject to change.

Returns:

array of size 2 containing 128-bit hash

finalize256

public long[] finalize256()

Computes the hash value after all bytes were processed. Invalidates the state. NOTE: The 256-bit HighwayHash algorithm is not yet frozen and subject to change.

Returns:

array of size 4 containing 256-bit hash

hash64

public static long hash64(byte[] data,
                          int offset,
                          int length,
                          long[] key)

NOTE: The 64-bit HighwayHash algorithm is declared stable and no longer subject to change.

Parameters:

data - array with data bytes

offset - position of first byte of data to read from

length - number of bytes from data to read

key - array of size 4 with the key to initialize the hash with

Returns:

64-bit hash for the given data

hash128

public static long[] hash128(byte[] data,
                             int offset,
                             int length,
                             long[] key)

NOTE: The 128-bit HighwayHash algorithm is not yet frozen and subject to change.

Parameters:

data - array with data bytes

offset - position of first byte of data to read from

length - number of bytes from data to read

key - array of size 4 with the key to initialize the hash with

Returns:

array of size 2 containing 128-bit hash for the given data

hash256

public static long[] hash256(byte[] data,
                             int offset,
                             int length,
                             long[] key)

NOTE: The 256-bit HighwayHash algorithm is not yet frozen and subject to change.

Parameters:

data - array with data bytes

offset - position of first byte of data to read from

length - number of bytes from data to read

key - array of size 4 with the key to initialize the hash with

Returns:

array of size 4 containing 256-bit hash for the given data