RocketMqConsumer 消费者使用范例

系统管理员 2022-10-28 04:56 142阅读 0赞

首先先了解下DefaultMQPushConsumer 参数：  
https://blog.csdn.net/weixin\_41715077/article/details/85170893  
以及消费模式：  
https://blog.csdn.net/qq\_36804701/article/details/81481343

简单例子

package com.swk.springboot.rocketmq;
    import java.util.List;
    import org.apache.rocketmq.client.consumer.DefaultMQPushConsumer;
    import org.apache.rocketmq.client.consumer.listener.ConsumeConcurrentlyContext;
    import org.apache.rocketmq.client.consumer.listener.ConsumeConcurrentlyStatus;
    import org.apache.rocketmq.client.consumer.listener.MessageListenerConcurrently;
    import org.apache.rocketmq.client.exception.MQClientException;
    import org.apache.rocketmq.common.consumer.ConsumeFromWhere;
    import org.apache.rocketmq.common.message.MessageExt;
    import org.apache.rocketmq.common.protocol.heartbeat.MessageModel;
    public class MQPushConsumer { 
        public static void main(String[] args) throws MQClientException { 
            String groupName = "rocketMqGroup1";
            // 用于把多个Consumer组织到一起，提高并发处理能力
            DefaultMQPushConsumer consumer = new DefaultMQPushConsumer(groupName);
            // 设置nameServer地址，多个以;分隔
            consumer.setNamesrvAddr("name-serverl-ip:9876;name-server2-ip:9876");
            /**
             * 1. CONSUME_FROM_LAST_OFFSET：第一次启动从队列最后位置消费，后续再启动接着上次消费的进度开始消费 
               2. CONSUME_FROM_FIRST_OFFSET：第一次启动从队列初始位置消费，后续再启动接着上次消费的进度开始消费 
               3. CONSUME_FROM_TIMESTAMP：第一次启动从指定时间点位置消费，后续再启动接着上次消费的进度开始消费 
                    以上所说的第一次启动是指从来没有消费过的消费者，如果该消费者消费过，那么会在broker端记录该消费者的消费位置，如果该消费者挂了再启动，那么自动从上次消费的进度开始
             */
            consumer.setConsumeFromWhere(ConsumeFromWhere.CONSUME_FROM_FIRST_OFFSET);
            /**
             * CLUSTERING：默认模式，同一个ConsumerGroup(groupName相同)每个consumer只消费所订阅消息的一部分内容，同一个ConsumerGroup里所有的Consumer消息加起来才是所
             *  订阅topic整体，从而达到负载均衡的目的
             * BROADCASTING：同一个ConsumerGroup每个consumer都消费到所订阅topic所有消息，也就是一个消费会被多次分发，被多个consumer消费。
             * 
             */
            consumer.setMessageModel(MessageModel.BROADCASTING);
            // 订阅topic，可以对指定消息进行过滤，例如："TopicTest","tagl||tag2||tag3",*或null表示topic所有消息
            consumer.subscribe("order-topic", "*");
            consumer.registerMessageListener(new MessageListenerConcurrently() { 
                
                @Override
                public ConsumeConcurrentlyStatus consumeMessage(List<MessageExt> mgs,
                        ConsumeConcurrentlyContext consumeconcurrentlycontext) { 
                    System.out.println(Thread.currentThread().getName()+"Receive New Messages:"+mgs);
                    // ConsumeConcurrentlyStatus.RECONSUME_LATER boker会根据设置的messageDelayLevel发起重试，默认16次
                    return ConsumeConcurrentlyStatus.CONSUME_SUCCESS;
                }
            });
            consumer.start();
        }
        
    }

实战例子

@Slf4j
    @Component
    public class RocketMqConsumer implements FactoryBean<DefaultMQPushConsumer>, InitializingBean, DisposableBean { 
    
        private DefaultMQPushConsumer consumer;
    
        private final MessageModel messageModel = MessageModel.CLUSTERING;
    
        @Autowired
        private YourService yourService;
    
        @Value("${rocketmq.consumer.groupName}")
        private String consumerGroupName;
        @Value("${rocketmq.consumer.instanceName}")
        private String instanceName;
        @Value("${rocketmq.consumer.nameServerAddr}")
        private String nameServerAddr;
        @Value("${rocketmq.consumer.consumeThreadMin}")
        private int consumeThreadMin;
        @Value("${rocketmq.consumer.consumeThreadMax}")
        private int consumeThreadMax;
        @Value("${rocketmq.consumer.subscribes.topicAndTags}")
        private String topicAndTags;
        @Value("${rocketmq.consumer.pullThresholdForQueue}")
        private int pullThresholdForQueue;
        @Value("${rocketmq.consumer.pullBatchSize}")
        private int pullBatchSize;
    
        @Override
        public void destroy() throws Exception { 
            if (null != this.consumer) { 
                consumer.shutdown();
                log.info("rocketMq consumer shutdown");
            }
        }
    
        @Override
        public DefaultMQPushConsumer getObject() throws Exception { 
            return this.consumer;
        }
    
        @Override
        public Class<?> getObjectType() { 
            return DefaultMQPushConsumer.class;
        }
    
        @Override
        public void afterPropertiesSet() throws Exception { 
            consumer = new DefaultMQPushConsumer(consumerGroupName);
            consumer.setInstanceName(instanceName);
            consumer.setMessageModel(messageModel);
            consumer.setNamesrvAddr(nameServerAddr);
            consumer.setConsumeThreadMax(consumeThreadMax);
            consumer.setConsumeThreadMin(consumeThreadMin);
            consumer.setPullBatchSize(pullBatchSize);
            consumer.setPullThresholdForQueue(pullThresholdForQueue);
            consumer.setConsumeFromWhere(ConsumeFromWhere.CONSUME_FROM_FIRST_OFFSET);
            // 订阅的 topic 和 tags
            consumer.subscribe(topicAndTags, topicAndTags);
            // 注册监听方式 有序
            consumer.registerMessageListener((MessageListenerOrderly) (messageExtList, consumeOrderlyContext) -> { MessageExt msg = messageExtList.get(0); String messageBody = new String(msg.getBody());
                log.info("consume message, msgId={}, topic={}, tags={}, keys={},\n body={}", msg.getMsgId(), msg.getTopic(), msg.getTags(), msg.getKeys(), messageBody);
                // todo: business code to consume message
               //yourService.xxx
                return ConsumeOrderlyStatus.SUCCESS;
            });
            consumer.start();
            log.info("rocketMQ consumer group [{}] started", consumerGroupName);
        }
    }