gov.loc.repository.bagit.hash

Class Hasher

java.lang.Object

gov.loc.repository.bagit.hash.Hasher

public final class Hasher
extends java.lang.Object

Convenience class for generating a HEX formatted string of the checksum hash.

Method Summary

Modifier and Type	Method and Description
static java.util.Map<Manifest,java.security.MessageDigest>	createManifestToMessageDigestMap(java.util.Collection<SupportedAlgorithm> algorithms) create a mapping between Manifest and MessageDigest for each each supplied SupportedAlgorithm
static void	hash(java.nio.file.Path path, java.util.Map<Manifest,java.security.MessageDigest> manifestToMessageDigestMap) Update the Manifests with the file's hash
static java.lang.String	hash(java.nio.file.Path path, java.security.MessageDigest messageDigest) Create a HEX formatted string checksum hash of the file

Methods inherited from class java.lang.Object

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

Method Detail

hash

public static java.lang.String hash(java.nio.file.Path path,
                                    java.security.MessageDigest messageDigest)
                             throws java.io.IOException

Create a HEX formatted string checksum hash of the file

Parameters:

path - the Path (file) to hash

messageDigest - the MessageDigest object representing the hashing algorithm

Returns:

the hash as a hex formated string

Throws:

java.io.IOException - if there is a problem reading the file

hash

public static void hash(java.nio.file.Path path,
                        java.util.Map<Manifest,java.security.MessageDigest> manifestToMessageDigestMap)
                 throws java.io.IOException

Update the Manifests with the file's hash

Parameters:

path - the Path (file) to hash

manifestToMessageDigestMap - the map between Manifest and MessageDigest

Throws:

java.io.IOException - if there is a problem reading the file

createManifestToMessageDigestMap

public static java.util.Map<Manifest,java.security.MessageDigest> createManifestToMessageDigestMap(java.util.Collection<SupportedAlgorithm> algorithms)
                                                                                            throws java.security.NoSuchAlgorithmException

create a mapping between Manifest and MessageDigest for each each supplied SupportedAlgorithm

Parameters:

algorithms - the SupportedAlgorithm that you which to map to MessageDigest

Returns:

mapping between Manifest and MessageDigest

Throws:

java.security.NoSuchAlgorithmException - if MessageDigest doesn't support the algorithm