@Test
  public void testPaymentAck() throws Exception {
    // Create
    Payment paymentMessage = Protos.Payment.newBuilder().build();
    PaymentACK paymentAck = PaymentProtocol.createPaymentAck(paymentMessage, MEMO);
    byte[] paymentAckBytes = paymentAck.toByteArray();

    // Parse
    PaymentACK parsedPaymentAck = PaymentACK.parseFrom(paymentAckBytes);
    assertEquals(paymentMessage, parsedPaymentAck.getPayment());
    assertEquals(MEMO, parsedPaymentAck.getMemo());
  }