<dependency> <groupId>org.apache.rocketmq</groupId> <artifactId>rocketmq-client</artifactId> <version>3.6.2</version> </dependency> import org.apache.rocketmq.client.producer.DefaultMQProducer; import org.apache.rocketmq.common.message.Message; public class RocketMQProducer { public static void main(String[] args) throws Exception { DefaultMQProducer producer = new DefaultMQProducer("producerGroup"); producer.setNamesrvAddr("localhost:9876"); producer.start(); Message message = new Message("topic", "tag", "Hello, RocketMQ!".getBytes()); producer.send(message); producer.shutdown(); } } import org.apache.rocketmq.client.consumer.DefaultMQPushConsumer; import org.apache.rocketmq.client.consumer.listener.MessageListenerConcurrently; import org.apache.rocketmq.client.consumer.listener.ConsumeConcurrentlyContext; import org.apache.rocketmq.common.message.MessageExt; import java.util.List; public class RocketMQConsumer { public static void main(String[] args) throws Exception { DefaultMQPushConsumer consumer = new DefaultMQPushConsumer("consumerGroup"); consumer.setNamesrvAddr("localhost:9876"); consumer.registerMessageListener((MessageListenerConcurrently) (messages, context) -> { for (MessageExt message : messages) { System.out.println(new String(message.getBody())); } return ConsumeConcurrentlyStatus.CONSUME_SUCCESS; }); consumer.subscribe("topic", "tag"); consumer.start(); } }