docs: private void initialize()
  		throws NoSuchAlgorithmException, NoSuchPaddingException, InvalidKeyException,
  		InvalidKeySpecException, IOException, InvalidAlgorithmParameterException
  	{
  		if (!isInitialized())
  		{
  			cipher = Cipher
  				.getInstance(KeyPairWithModeAndPaddingAlgorithm.RSA_ECB_OAEPWithSHA1AndMGF1Padding
  					.getAlgorithm());
  			cipher.init(Cipher.DECRYPT_MODE, privateKey);
  			initialized = true;
  		}
  	}