docs: public SendResult send(MessageBuilder builder, long timeout, TimeUnit unit) throws InterruptedException {
          Message msg = builder.build(this.messageBodyConverter);
          final String topic = msg.getTopic();
          MessageProducer producer = this.getOrCreateProducer(topic);
          try {
              return producer.sendMessage(msg, timeout, unit);
          }
          catch (MetaClientException e) {
              return new SendResult(false, null, -1, ExceptionUtils.getFullStackTrace(e));
          }
      }