generateIv.java

private static final String RANDOM_ALGORITHM = "SHA1PRNG";
public static final int IV_LENGTH = 16;

private byte[] generateIv() throws NoSuchAlgorithmException, NoSuchProviderException {
            SecureRandom random = SecureRandom.getInstance(RANDOM_ALGORITHM);
            byte[] iv = new byte[IV_LENGTH];
            random.nextBytes(iv);
            return iv;
    }