org.bouncycastle.tsp.ers

Class ERSDataGroup

java.lang.Object

org.bouncycastle.tsp.ers.ERSCachingData

org.bouncycastle.tsp.ers.ERSDataGroup

All Implemented Interfaces:

ERSData

Direct Known Subclasses:

ERSDirectoryDataGroup

public class ERSDataGroup
extends ERSCachingData

Representation of data groups with more than 1 members according to the description provided in RFC4998.

Such data groups represent a set of one or more data objects (e.g. electronic documents) for which an Evidence Record should be generated. Data groups will be encapsulated in a single PartialHashtree so that the presence of the group can be checked for, as well as the individual items that make it up.

Field Summary

Fields

Modifier and Type	Field and Description
protected java.util.List<ERSData>	dataObjects

Constructor Summary

Constructors

Constructor and Description
ERSDataGroup(ERSData... dataObjects) Base constructor for an "array" of data objects.
ERSDataGroup(ERSData dataObject) Constructor for a group with a single object.
ERSDataGroup(java.util.List<ERSData> dataObjects) Base constructor using a list of data objects.

Method Summary

Modifier and Type	Method and Description
protected byte[]	calculateHash(DigestCalculator digestCalculator, byte[] previousChainHash) Generates a hash for the whole DataGroup.
byte[]	getHash(DigestCalculator digestCalculator, byte[] previousChainHash) Return the calculated hash for the Data
java.util.List<byte[]>	getHashes(DigestCalculator digestCalculator, byte[] previousChainHash) Generates hashes for all the data objects included in the data group with a previous chain hash.
int	size() Return the number of data objects present in the group.

Methods inherited from class java.lang.Object

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

Field Detail

dataObjects

protected java.util.List<ERSData> dataObjects

Constructor Detail

ERSDataGroup

public ERSDataGroup(ERSData... dataObjects)

Base constructor for an "array" of data objects.

Parameters:

dataObjects - an array of data objects.

ERSDataGroup

public ERSDataGroup(java.util.List<ERSData> dataObjects)

Base constructor using a list of data objects.

Parameters:

dataObjects - a list of data objects.

ERSDataGroup

public ERSDataGroup(ERSData dataObject)

Constructor for a group with a single object.

Parameters:

dataObject - the data object to go in the group.

Method Detail

getHashes

public java.util.List<byte[]> getHashes(DigestCalculator digestCalculator,
                                        byte[] previousChainHash)

Generates hashes for all the data objects included in the data group with a previous chain hash.

Parameters:

digestCalculator - the DigestCalculator to use for computing the hashes

Returns:

the set of hashes, in ascending order

getHash

public byte[] getHash(DigestCalculator digestCalculator,
                      byte[] previousChainHash)

Return the calculated hash for the Data

Specified by:

getHash in interface ERSData

Overrides:

getHash in class ERSCachingData

Parameters:

digestCalculator - digest calculator to use.

previousChainHash - hash from an earlier chain if it needs to be included.

Returns:

calculated hash.

calculateHash

protected byte[] calculateHash(DigestCalculator digestCalculator,
                               byte[] previousChainHash)

Generates a hash for the whole DataGroup.

Specified by:

calculateHash in class ERSCachingData

Parameters:

digestCalculator - the DigestCalculator to use for computing the hash

Returns:

a hash that is representative of the whole DataGroup

size

public int size()

Return the number of data objects present in the group.

Returns:

membership count of the group.