Client createClient(final ClientId clientId, final VerificationKey verificationKey) {
   final Client client = new Client();
   client.setComparisonIdentities(new ArrayList<>());
   client.setDeviceToken(clientId.getClient());
   final PublicKeys publicKeys = new PublicKeys();
   publicKeys.setVerification(verificationKey);
   final EncryptionKey encryptionKey = new EncryptionKey();
   encryptionKey.setAlgorithm(EncryptionAlgorithm.RSA2048);
   final ByteBuffer b = ByteBuffer.wrap("".getBytes());
   b.mark();
   encryptionKey.setBuffer(b);
   publicKeys.setEncryption(encryptionKey);
   client.setKeys(publicKeys);
   final UserAgent userAgent = new UserAgent();
   userAgent.setPlatform("");
   userAgent.setVersion("");
   client.setUserAgent(userAgent);
   return client;
 }