Here you can find the source of randomIVString()
public static String randomIVString()
//package com.java2s; import java.security.SecureRandom; import java.math.BigInteger; public class Main { private static final SecureRandom random = new SecureRandom(); public static String randomIVString() { return new BigInteger(130, random).toString(16); }//www . j a v a 2 s.co m }