io.milton.zsync

Class Generator

java.lang.Object

io.milton.zsync.Generator

public class Generator
extends Object

Checksum generation methods.

Version:

$Revision: 1.12 $

Constructor Summary

Constructors

Constructor and Description
Generator()

Method Summary

Modifier and Type	Method and Description
int	generateRollSum(byte b, Configuration config)
byte[]	generateStrongSum(byte[] buf, int off, int len, Configuration config)
ChecksumPair	generateSum(byte[] buf, int off, int len, long fileOffset, Configuration config) Generate a sum pair for a portion of a byte array.
ChecksumPair	generateSum(byte[] buf, long fileOffset, Configuration config) Generate a sum pair for an entire byte array.
List	generateSums(byte[] buf, long baseOffset, Configuration config) Generate checksums over an entire byte array, with a specified base offset.
List	generateSums(File f, Configuration config) Generate checksums for an entire file.
List	generateSums(InputStream in, Configuration config, MessageDigest sha1) Generate checksums for an InputStream.
int	generateWeakSum(byte[] buf, int offset, Configuration config)

Methods inherited from class java.lang.Object

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

Constructor Detail

Generator

public Generator()

Method Detail

generateSums

public List generateSums(byte[] buf,
                         long baseOffset,
                         Configuration config)

Generate checksums over an entire byte array, with a specified base offset. This baseOffset is added to the offset stored in each ChecksumPair.

Parameters:

buf - The byte array to checksum.

baseOffset - The offset from whence this byte array came.

Returns:

A List of ChecksumPairs generated from the array.

See Also:

#generateSums(byte[],int,int,long)

generateSums

public List generateSums(File f,
                         Configuration config)
                  throws IOException

Generate checksums for an entire file.

Parameters:

f - The File to checksum.

Returns:

A List of ChecksumPairs generated from the file.

Throws:

IOException - if f cannot be read from.

generateSums

public List generateSums(InputStream in,
                         Configuration config,
                         MessageDigest sha1)
                  throws IOException,
                         NoSuchAlgorithmException

Generate checksums for an InputStream.

Parameters:

in - The InputStream to checksum.

Returns:

A List of ChecksumPairs generated from the bytes read.

Throws:

IOException - if reading fails.

NoSuchAlgorithmException

generateSum

public ChecksumPair generateSum(byte[] buf,
                                long fileOffset,
                                Configuration config)

Generate a sum pair for an entire byte array.

Parameters:

buf - The byte array to checksum.

fileOffset - The offset in the original file from whence this block came.

Returns:

A ChecksumPair for this byte array.

generateSum

public ChecksumPair generateSum(byte[] buf,
                                int off,
                                int len,
                                long fileOffset,
                                Configuration config)

Generate a sum pair for a portion of a byte array.

Parameters:

buf - The byte array to checksum.

off - Where in buf to start.

len - How many bytes to checksum.

fileOffset - The original offset of this byte array.

Returns:

A ChecksumPair for this byte array.

generateWeakSum

public int generateWeakSum(byte[] buf,
                           int offset,
                           Configuration config)

generateRollSum

public int generateRollSum(byte b,
                           Configuration config)

generateStrongSum

public byte[] generateStrongSum(byte[] buf,
                                int off,
                                int len,
                                Configuration config)