com.amazonaws.services.glacier

Class TreeHashGenerator

java.lang.Object

com.amazonaws.services.glacier.TreeHashGenerator

public class TreeHashGenerator
extends Object

Utility class for calculating tree hashes.

For more information on tree hashing, see http://en.wikipedia.org/wiki/Hash_tree.

Constructor Summary

Constructors

Constructor and Description
TreeHashGenerator()

Method Summary

Methods

Modifier and Type	Method and Description
static String	calculateTreeHash(File file) Calculates a hex encoded binary hash using a tree hashing algorithm for the data in the specified file.
static String	calculateTreeHash(InputStream input) Calculates a hex encoded binary hash using a tree hashing algorithm for the data in the specified input stream.
static String	calculateTreeHash(List<byte[]> checksums) Returns the hex encoded binary tree hash for the individual checksums given.

Methods inherited from class java.lang.Object

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

Constructor Detail

TreeHashGenerator

public TreeHashGenerator()

Method Detail

calculateTreeHash

public static String calculateTreeHash(File file)
                                throws AmazonClientException

Calculates a hex encoded binary hash using a tree hashing algorithm for the data in the specified file.

Parameters:

file - The file containing the data to hash.

Returns:

The hex encoded binary tree hash for the data in the specified file.

Throws:

AmazonClientException - If any problems were encountered reading the data or computing the hash.

calculateTreeHash

public static String calculateTreeHash(InputStream input)
                                throws AmazonClientException

Calculates a hex encoded binary hash using a tree hashing algorithm for the data in the specified input stream. The method will consume all the inputStream and close it when returned.

Parameters:

input - The input stream containing the data to hash.

Returns:

The hex encoded binary tree hash for the data in the specified input stream.

Throws:

AmazonClientException - If problems were encountered reading the data or calculating the hash.

calculateTreeHash

public static String calculateTreeHash(List<byte[]> checksums)
                                throws AmazonClientException

Returns the hex encoded binary tree hash for the individual checksums given. The sums are assumed to have been generated from sequential 1MB portions of a larger file, with the possible exception of the last part, which may be less than a full MB.

Returns:

The combined hex encoded binary tree hash for the individual checksums specified.

Throws:

AmazonClientException - If problems were encountered reading the data or calculating the hash.