this is my pom file: 
 <!--RocketMQ-->
    <dependency>
        <groupId>org.apache.rocketmq</groupId>
        <artifactId>rocketmq-client</artifactId>
        <version>4.4.0</version>
    </dependency>

   @Autowired
    private DefaultMQProducer defaultMQProducer;

   ...

   defaultMQProducer.send(message);