Code example for SecureRandom

Methods: nextLong

	 * Generates a nonce (a random number used once). 
	 * @return the nonce 
	public static long generateNonce() { 
		long nonce = RANDOM.nextLong();
		return nonce;
	public static void removeNonce(long nonce) {
	public static boolean isNonceKnown(long nonce) {
		return knownNonces.contains(nonce);
	 * Verifies that the data was signed with the given signature, and returns the list of verified purchases. The data 
	 * is in JSON format and contains a nonce (number used once) that we generated and that was signed (as part of the