eu.unicore.uftp.rsync

Class Checksum

java.lang.Object

eu.unicore.uftp.rsync.Checksum

public class Checksum
extends Object

Helper class for dealing with the checksums used in rsync
Based on Andrew Tridgell's 'rsync' as described in http://cs.anu.edu.au/techreports/1996/TR-CS-96-05.pdf

Author:

schuller

Constructor Summary

Constructors

Constructor and Description
Checksum()

Method Summary

Modifier and Type	Method and Description
static long	a(byte[] block) the function "a" from the rsync rolling checksum algorithm
static long	b(byte[] block, long k, long l) the function "b" from the rsync algorithm
static long	checksum(byte[] block, long start, long finish) compute the checksum for the given data block
static byte[]	md5(byte[] block)
static long	sum(long a, long b)

Methods inherited from class java.lang.Object

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

Constructor Detail

Checksum

public Checksum()

Method Detail

a

public static long a(byte[] block)

the function "a" from the rsync rolling checksum algorithm

Parameters:

block -

Returns:

b

public static long b(byte[] block,
                     long k,
                     long l)

the function "b" from the rsync algorithm

Parameters:

block -

k - - start

l - - finish

Returns:

sum

public static long sum(long a,
                       long b)

checksum

public static long checksum(byte[] block,
                            long start,
                            long finish)

compute the checksum for the given data block

Parameters:

block - - data

start - - start index of the block in the complete data

finish - - end index of the block in the complete data

Returns:

checksum

md5

public static byte[] md5(byte[] block)