@Override
            public void onSuccess(SendResult var1) {
                System.out.printf("async onSuccess SendResult=%s %n", var1);
            }
Producer, using RocketMQTemplate sends a variety of messages
rocketmq-spring-boot-samples/rocketmq-produce-demo/src/main/java/org/apache/rocketmq/samples/springboot/ProducerApplication.java