code: public static byte[] generateKey() {
          CipherKeyGenerator cipherKeyGenerator = new CipherKeyGenerator();
          cipherKeyGenerator.init(new KeyGenerationParameters(new SecureRandom(), 128));
          return cipherKeyGenerator.generateKey();
      }
docs: Generates a 128-bit key (16 bytes) randomly for RC4 encryption/decryption.
  
  @return generated key bytes