de.upb.swtpra05.group03.crypto
Class SharedSeedRNG

java.lang.Object
  de.upb.swtpra05.group03.crypto.SharedSeedRNG

public class SharedSeedRNG

extends java.lang.Object

provides random number generators all with the same seed

Version:

$Revision: 1.3 $

Field Summary

protected static java.lang.String	ALGORITHM algorithm used by the pseudo random number generator
protected static java.lang.String	HOME_DIR home directory of the user
protected static byte[]	SEED common seed used by all shuttles
protected static java.io.File	SEED_DIR our settings dir to save the seed in
protected static java.io.File	SEED_FILE file to save the seed in

Constructor Summary

SharedSeedRNG()

Method Summary

static java.security.SecureRandom	getRandom() returns a random number generator seeded with the common seed
protected static byte[]	loadSeed() load the seed from the seed file
static void	saveSeed(byte[] seed) saves a seed into the seed file

Methods inherited from class java.lang.Object

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

Field Detail

HOME_DIR

protected static final java.lang.String HOME_DIR

home directory of the user

SEED_DIR

protected static final java.io.File SEED_DIR

our settings dir to save the seed in

SEED_FILE

protected static final java.io.File SEED_FILE

file to save the seed in

ALGORITHM

protected static final java.lang.String ALGORITHM

algorithm used by the pseudo random number generator

See Also:

Constant Field Values

SEED

protected static final byte[] SEED

common seed used by all shuttles

Constructor Detail

SharedSeedRNG

public SharedSeedRNG()

Method Detail

getRandom

public static java.security.SecureRandom getRandom()
                                            throws java.security.NoSuchAlgorithmException

returns a random number generator seeded with the common seed

Returns:

random number generator

Throws:

java.security.NoSuchAlgorithmException

saveSeed

public static void saveSeed(byte[] seed)

saves a seed into the seed file

Parameters:

seed - seed as a bytearray

loadSeed

protected static byte[] loadSeed()

load the seed from the seed file

Returns:

seed as a bytearray