Package org.klomp.snark.v2

Class V2Util

java.lang.Object

org.klomp.snark.v2.V2Util

public class V2Util
extends Object

Merkle utilities

Since:

0.9.71

Field Summary

Fields

Modifier and Type	Field	Description
static final int	MIN

Constructor Summary

Constructors

Constructor	Description
V2Util()

Method Summary

Modifier and Type	Method	Description
static List<MerkleHash>	calculateMerklePieces(File f, int plen)
static List<MerkleHash>	calculateMerklePieces(InputStream in, int plen)	Warn, will return bad value for files if plen is greater than the next power of two of the input size
static MerkleHash	calculateMerkleRoot(byte[] b, int plen)
static MerkleHash	calculateMerkleRoot(File f)
static MerkleHash	calculateMerkleRoot(InputStream in, int plen)	Warn, will return bad value for files if plen is greater than the next power of two of the input size
static MerkleHash	calculateMerkleRoot(List<MerkleHash> pieces, int plen)
static boolean	checkMerkle(MerkleHash root, List<MerkleHash> pieces, int plen)
static boolean	isValidPieceLength(int plen)	16K min and power of two Storage.MAX_PIECE_SIZE is checked elsewhere but do it here also.
static void	main(String[] args)
static int	rectify(long flen)
static int	rectify(long flen, int plen)

Methods inherited from class java.lang.Object

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

Field Details

MIN

public static final int MIN

See Also:

• Constant Field Values

Constructor Details

V2Util

public V2Util()

Method Details

isValidPieceLength

public static boolean isValidPieceLength(int plen)

16K min and power of two Storage.MAX_PIECE_SIZE is checked elsewhere but do it here also.

rectify

public static int rectify(long flen)

Parameters:

flen - the file length

Returns:

next power of two of flen, or 0 if flen is 0

rectify

public static int rectify(long flen,
 int plen)

Parameters:

flen - the file length

plen - piece length, 16K minimum, power of two, or zero

Returns:

plen, or next power of two of flen if smaller, or 0 if flen is 0

checkMerkle

public static boolean checkMerkle(MerkleHash root,
 List<MerkleHash> pieces,
 int plen)

Parameters:

pieces - two minimum

plen - piece length, 16K minimum, power of two

calculateMerkleRoot

public static MerkleHash calculateMerkleRoot(List<MerkleHash> pieces,
 int plen)

Parameters:

pieces - two minimum

plen - piece length, 16K minimum, power of two

calculateMerkleRoot

public static MerkleHash calculateMerkleRoot(File f)
                                      throws IOException

Returns:

the root hash

Throws:

IOException

calculateMerkleRoot

public static MerkleHash calculateMerkleRoot(byte[] b,
 int plen)
                                      throws IOException

Parameters:

plen - piece length, for pieces, MUST be the full padded piece length

Returns:

the root hash

Throws:

IOException

calculateMerkleRoot

public static MerkleHash calculateMerkleRoot(InputStream in,
 int plen)
                                      throws IOException

Warn, will return bad value for files if plen is greater than the next power of two of the input size

Parameters:

plen - piece length, for files, MUST be rectified to next power of two with rectify(); for pieces, MUST be the full padded piece length

Returns:

the root hash

Throws:

IOException

calculateMerklePieces

public static List<MerkleHash> calculateMerklePieces(File f,
 int plen)
                                              throws IOException

Parameters:

plen - will use only if smaller than file size

Returns:

the piece hashes

Throws:

IOException

calculateMerklePieces

public static List<MerkleHash> calculateMerklePieces(InputStream in,
 int plen)
                                              throws IOException

Warn, will return bad value for files if plen is greater than the next power of two of the input size

Parameters:

plen - piece length, for files, MUST be rectified to next power of two with rectify(); for pieces, MUST be the full padded piece length

Returns:

the piece hashes

Throws:

IOException

main

public static void main(String[] args)
                 throws Exception

Throws:

Exception