Package org.apache.commons.codec.digest

Class XXHash32

java.lang.Object

org.apache.commons.codec.digest.XXHash32

All Implemented Interfaces:

java.util.zip.Checksum

public class XXHash32
extends java.lang.Object
implements java.util.zip.Checksum

Implementation of the xxhash32 hash algorithm.

Copied from Commons Compress 1.14 https://git-wip-us.apache.org/repos/asf?p=commons-compress.git;a=blob;f=src/main/java/org/apache/commons/compress/compressors/lz4/XXHash32.java;h=a406ffc197449be594d46f0d2712b2d4786a1e68;hb=HEAD

NotThreadSafe

Since:

1.11

See Also:

xxHash

Field Summary

Fields

Modifier and Type	Field	Description
private static int	BUF_SIZE
private byte[]	buffer
private byte[]	oneByte
private int	pos
private static int	PRIME1
private static int	PRIME2
private static int	PRIME3
private static int	PRIME4
private static int	PRIME5
private static int	ROTATE_BITS
private int	seed
private int[]	state
private boolean	stateUpdated	Set to true when the state array has been updated since the last reset.
private int	totalLen

Constructor Summary

Constructors

Constructor	Description
XXHash32()	Creates an XXHash32 instance with a seed of 0.
XXHash32(int seed)	Creates an XXHash32 instance.

Method Summary

Modifier and Type	Method	Description
private static int	getInt(byte[] buffer, int idx)	Gets the little-endian int from 4 bytes starting at the specified index.
long	getValue()
private void	initializeState()
private void	process(byte[] b, int offset)
void	reset()
void	update(byte[] b, int off, int len)
void	update(int b)

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.zip.Checksum

update, update

Field Detail

BUF_SIZE

private static final int BUF_SIZE

See Also:

Constant Field Values

ROTATE_BITS

private static final int ROTATE_BITS

See Also:

Constant Field Values

PRIME1

private static final int PRIME1

See Also:

Constant Field Values

PRIME2

private static final int PRIME2

See Also:

Constant Field Values

PRIME3

private static final int PRIME3

See Also:

Constant Field Values

PRIME4

private static final int PRIME4

See Also:

Constant Field Values

PRIME5

private static final int PRIME5

See Also:

Constant Field Values

oneByte

private final byte[] oneByte

state

private final int[] state

buffer

private final byte[] buffer

seed

private final int seed

totalLen

private int totalLen

pos

private int pos

stateUpdated

private boolean stateUpdated

Set to true when the state array has been updated since the last reset.

Constructor Detail

XXHash32

public XXHash32()

Creates an XXHash32 instance with a seed of 0.

XXHash32

public XXHash32(int seed)

Creates an XXHash32 instance.

Parameters:

seed - the seed to use

Method Detail

reset

public void reset()

Specified by:

reset in interface java.util.zip.Checksum

update

public void update(int b)

Specified by:

update in interface java.util.zip.Checksum

update

public void update(byte[] b,
                   int off,
                   int len)

Specified by:

update in interface java.util.zip.Checksum

getValue

public long getValue()

Specified by:

getValue in interface java.util.zip.Checksum

getInt

private static int getInt(byte[] buffer,
                          int idx)

Gets the little-endian int from 4 bytes starting at the specified index.

Parameters:

buffer - The data

idx - The index

Returns:

The little-endian int

initializeState

private void initializeState()

process

private void process(byte[] b,
                     int offset)