Package org.apache.commons.codec.digest

Class MurmurHash3.IncrementalHash32x86

java.lang.Object

org.apache.commons.codec.digest.MurmurHash3.IncrementalHash32x86

Direct Known Subclasses:

MurmurHash3.IncrementalHash32

Enclosing class:

MurmurHash3

public static class MurmurHash3.IncrementalHash32x86
extends Object

Generates 32-bit hash from input bytes. Bytes can be added incrementally and the new hash computed.

This is an implementation of the 32-bit hash function MurmurHash3_x86_32 from from Austin Applyby's original MurmurHash3 c++ code in SMHasher.

Since:

1.14

Constructor Summary

Constructors

Constructor	Description
IncrementalHash32x86()

Method Summary

Modifier and Type	Method	Description
void	add(byte[] data, int offset, int length)	Adds the byte array to the current incremental hash.
int	end()	Generate the 32-bit hash value.
(package private) int	finalise(int hash, int unprocessedLength, byte[] unprocessed, int totalLen)	Finalize the running hash to the output 32-bit hash by processing remaining bytes and performing final mixing.
void	start(int seed)	Starts a new incremental hash.

Methods inherited from class java.lang.Object

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

Constructor Detail

IncrementalHash32x86

public IncrementalHash32x86()

Method Detail

start

public final void start(int seed)

Starts a new incremental hash.

Parameters:

seed - The initial seed value

add

public final void add(byte[] data,
                      int offset,
                      int length)

Adds the byte array to the current incremental hash.

Parameters:

data - The input byte array

offset - The offset of data

length - The length of array

end

public final int end()

Generate the 32-bit hash value. Repeat calls to this method with no additional data will generate the same hash value.

Returns:

The 32-bit hash

finalise

int finalise(int hash,
             int unprocessedLength,
             byte[] unprocessed,
             int totalLen)

Finalize the running hash to the output 32-bit hash by processing remaining bytes and performing final mixing.

Parameters:

hash - The running hash

unprocessedLength - The number of unprocessed bytes in the tail data.

unprocessed - Up to 3 unprocessed bytes from input data.

totalLen - The total number of input bytes added since the start.

Returns:

The 32-bit hash