is it possible to get the group name from registerMessageListener in RocketMQ

Question

I am using RocketMQ as the message center, this is the consumer dependencies jar:

<dependency>
            <groupId>org.apache.rocketmq</groupId>
            <artifactId>rocketmq-client</artifactId>
            <version>4.9.1</version>
        </dependency>

this is part of the conumser code:

consumer.registerMessageListener(new MessageListenerConcurrently() {
            @Override
            public ConsumeConcurrentlyStatus consumeMessage(List<MessageExt> msgs, ConsumeConcurrentlyContext context) {
                for (MessageExt message : msgs) {
                    String params = new String(message.getBody(), StandardCharsets.UTF_8);
                    ObjectMapper mapper = new ObjectMapper();
                    try {
                        Map<String, Object> parameters = mapper.readValue(params, Map.class);
                        String messageTopic = context.getMessageQueue().getTopic();
                        // what should I do to get the group name ?
                    } catch (JsonProcessingException e) {
                        throw new RuntimeException(e);
                    }
                }
                return ConsumeConcurrentlyStatus.CONSUME_SUCCESS;
            }
        });
        consumer.start();

in this code block, I want to get the consumerGroup name, I tracing into the ConsumeConcurrentlyContext class and only found the topic, did not found the consumerGroup name. is it possible to get the consumerGroup name from the registerMessageListener block?

Answer 1

Actually you needn't. Since you can already got the consumer group name in the callback method from your consumer instance by

consumer.getConsumerGroup().

Maybe you will need to define a non-anonymous instance for the listener.

You can try

public class MyMessageListenerConcurrently implements MessageListenerConcurrently{
    private String consumerGroupName;
    public MyMessageListenerConcurrently(String consumerGroupName) {
        this.consumerGroupName = consumerGroupName
    }
    ....
}

And when you register:

    consumer.registerMessageListener(new MyMessageListenerConcurrently(consumer.getConsumerGroup()));