系列九、Java操作RocketMQ之顺序消息

一、概述

        消息有序指的是可以按照消息发送的顺序来消费（FIFO），RocketMQ可以严格的保证消息有序，按照分区的不同，可以分为分区有序和全局有序。顺序消费的原理解析，在默认情况下消息发送会按照轮询的方式把消息发送到不同的Queue中（说明：一个Broker中有四个Queue），消费者消费消息的时候会从多个Queue上拉取消息，这种情况下消费者是无法顺序消费生产者发送的消息的。但是如果控制发送的顺序消息只依次发送到同一个Queue中，那么消费的时候只能从这个Queue上拉取，这种方式即为全局有序，虽然保证了顺序消费，但是效率比较低。再说说分区有序，分区有序是指有多个Queue参与，相对于每个Queue，消息都是有序的，可以类比当前网购的流程，一般都是：创建订单==》扣减库存==》增加积分，下面参考案例代码

二、案例代码

2.1、pom

        同案例五

2.2、RocketMQConstant

        同案例五

2.3、消费者

2.3.1、DLJDOrderConsumer1

package org.star.orderly.consumer;import cn.hutool.core.util.StrUtil;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.collections4.CollectionUtils;
import org.apache.rocketmq.client.consumer.DefaultMQPushConsumer;
import org.apache.rocketmq.client.consumer.listener.ConsumeOrderlyContext;
import org.apache.rocketmq.client.consumer.listener.ConsumeOrderlyStatus;
import org.apache.rocketmq.client.consumer.listener.MessageListenerOrderly;
import org.apache.rocketmq.common.message.MessageExt;
import org.star.constants.RocketMQConstant;import java.util.List;/*** @Author: 一叶浮萍归大海* @Date: 2023/8/25 16:23* @Description: 顺序消息消费者*/
@Slf4j
public class DLJDOrderConsumer1 {public static void main(String[] args) throws Exception {DefaultMQPushConsumer consumer = new DefaultMQPushConsumer("DLJDOrderConsumerGroup");consumer.setNamesrvAddr(RocketMQConstant.NAME_SERVER_ADDR);consumer.subscribe("DLJDOrderTopic", "*");consumer.registerMessageListener(new MessageListenerOrderly() {@Overridepublic ConsumeOrderlyStatus consumeMessage(List<MessageExt> list, ConsumeOrderlyContext consumeOrderlyContext) {if (CollectionUtils.isNotEmpty(list)) {list.forEach(e -> {log.info("我是消费者DLJDOrderConsumer1，当前线程：{}，队列ID：{}，收到消息：{}",Thread.currentThread().getName(),e.getQueueId(), StrUtil.utf8Str(e.getBody()));});}return ConsumeOrderlyStatus.SUCCESS;}});consumer.start();log.info("DLJDOrderConsumer1 start success");}}

2.3.2、DLJDOrderConsumer2

package org.star.orderly.consumer;import cn.hutool.core.util.StrUtil;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.collections4.CollectionUtils;
import org.apache.rocketmq.client.consumer.DefaultMQPushConsumer;
import org.apache.rocketmq.client.consumer.listener.ConsumeOrderlyContext;
import org.apache.rocketmq.client.consumer.listener.ConsumeOrderlyStatus;
import org.apache.rocketmq.client.consumer.listener.MessageListenerOrderly;
import org.apache.rocketmq.common.message.MessageExt;
import org.star.constants.RocketMQConstant;import java.util.List;/*** @Author: 一叶浮萍归大海* @Date: 2023/8/25 16:23* @Description: 顺序消息消费者*/
@Slf4j
public class DLJDOrderConsumer2 {public static void main(String[] args) throws Exception {DefaultMQPushConsumer consumer = new DefaultMQPushConsumer("DLJDOrderConsumerGroup");consumer.setNamesrvAddr(RocketMQConstant.NAME_SERVER_ADDR);consumer.subscribe("DLJDOrderTopic", "*");consumer.registerMessageListener(new MessageListenerOrderly() {@Overridepublic ConsumeOrderlyStatus consumeMessage(List<MessageExt> list, ConsumeOrderlyContext consumeOrderlyContext) {if (CollectionUtils.isNotEmpty(list)) {list.forEach(e -> {log.info("我是消费者DLJDOrderConsumer2，当前线程：{}，队列ID：{}，收到消息：{}",Thread.currentThread().getName(),e.getQueueId(), StrUtil.utf8Str(e.getBody()));});}return ConsumeOrderlyStatus.SUCCESS;}});consumer.start();log.info("DLJDOrderConsumer2 start success");}}

2.4、DLJDOrderProducer

package org.star.orderly.producer;import cn.hutool.core.util.StrUtil;
import com.alibaba.fastjson.JSON;
import lombok.extern.slf4j.Slf4j;
import org.apache.rocketmq.client.producer.DefaultMQProducer;
import org.apache.rocketmq.client.producer.MessageQueueSelector;
import org.apache.rocketmq.common.message.Message;
import org.apache.rocketmq.common.message.MessageQueue;
import org.star.constants.RocketMQConstant;import java.nio.charset.StandardCharsets;
import java.util.List;/*** @Author: 一叶浮萍归大海* @Date: 2023/8/25 16:14* @Description: 顺序消息生产者*/
@Slf4j
public class DLJDOrderProducer {public static void main(String[] args) throws Exception {DefaultMQProducer producer = new DefaultMQProducer("DLJDOrderProducerGroup");producer.setNamesrvAddr(RocketMQConstant.NAME_SERVER_ADDR);try {producer.start();// 模拟6笔订单for (Integer orderId = 1; orderId <= 6; orderId++) {// 每笔订单要发送3条消息，即：创建订单==》扣减库存==》增加积分for (int j = 0; j < 3; j++) {String data = "";switch (j % 3) {case 0:data = "创建订单，订单id：" + orderId;break;case 1:data = "扣减库存，订单id：" + orderId;break;case 2:data = "增加积分，订单id：" + orderId;break;}Message message = new Message("DLJDOrderTopic", "DLJDOrderTag", orderId.toString(), data.getBytes(StandardCharsets.UTF_8));producer.send(message, new MessageQueueSelector() {@Overridepublic MessageQueue select(List<MessageQueue> messageQueues, Message message, Object o) {int hashCode = message.getKeys().hashCode();int size = messageQueues.size();    // 队列的数量int index = hashCode % size;         // 队列的索引log.info("keys：{}，hashCode：{}，size：{}，index：{}，messageQueues：{}", message.getKeys(), hashCode, size, index, JSON.toJSONString(message));log.info("当前操作：{}", StrUtil.utf8Str(message.getBody()));return messageQueues.get(index);}}, orderId);}}log.info("DLJDOrderProducer start success");producer.shutdown();} catch (Exception e) {log.error("error:{}", e.getMessage());}}}

2.5、控制台打印

# 生产者端
22:03:41.819 [main] INFO org.star.orderly.producer.DLJDOrderProducer - keys：1，hashCode：49，size：4，index：1，messageQueues：{"body":"5Yib5bu66K6i5Y2V77yM6K6i5Y2VaWTvvJox","delayTimeLevel":0,"flag":0,"keys":"1","properties":{"KEYS":"1","WAIT":"true","TAGS":"DLJDOrderTag"},"tags":"DLJDOrderTag","topic":"DLJDOrderTopic","waitStoreMsgOK":true}
22:03:41.829 [main] INFO org.star.orderly.producer.DLJDOrderProducer - 当前操作：创建订单，订单id：1
22:03:43.235 [main] INFO org.star.orderly.producer.DLJDOrderProducer - keys：1，hashCode：49，size：4，index：1，messageQueues：{"body":"5omj5YeP5bqT5a2Y77yM6K6i5Y2VaWTvvJox","delayTimeLevel":0,"flag":0,"keys":"1","properties":{"KEYS":"1","WAIT":"true","TAGS":"DLJDOrderTag"},"tags":"DLJDOrderTag","topic":"DLJDOrderTopic","waitStoreMsgOK":true}
22:03:43.235 [main] INFO org.star.orderly.producer.DLJDOrderProducer - 当前操作：扣减库存，订单id：1
22:03:43.241 [main] INFO org.star.orderly.producer.DLJDOrderProducer - keys：1，hashCode：49，size：4，index：1，messageQueues：{"body":"5aKe5Yqg56ev5YiG77yM6K6i5Y2VaWTvvJox","delayTimeLevel":0,"flag":0,"keys":"1","properties":{"KEYS":"1","WAIT":"true","TAGS":"DLJDOrderTag"},"tags":"DLJDOrderTag","topic":"DLJDOrderTopic","waitStoreMsgOK":true}
22:03:43.241 [main] INFO org.star.orderly.producer.DLJDOrderProducer - 当前操作：增加积分，订单id：1
22:03:43.243 [main] INFO org.star.orderly.producer.DLJDOrderProducer - keys：2，hashCode：50，size：4，index：2，messageQueues：{"body":"5Yib5bu66K6i5Y2V77yM6K6i5Y2VaWTvvJoy","delayTimeLevel":0,"flag":0,"keys":"2","properties":{"KEYS":"2","WAIT":"true","TAGS":"DLJDOrderTag"},"tags":"DLJDOrderTag","topic":"DLJDOrderTopic","waitStoreMsgOK":true}
22:03:43.244 [main] INFO org.star.orderly.producer.DLJDOrderProducer - 当前操作：创建订单，订单id：2
22:03:43.247 [main] INFO org.star.orderly.producer.DLJDOrderProducer - keys：2，hashCode：50，size：4，index：2，messageQueues：{"body":"5omj5YeP5bqT5a2Y77yM6K6i5Y2VaWTvvJoy","delayTimeLevel":0,"flag":0,"keys":"2","properties":{"KEYS":"2","WAIT":"true","TAGS":"DLJDOrderTag"},"tags":"DLJDOrderTag","topic":"DLJDOrderTopic","waitStoreMsgOK":true}
22:03:43.247 [main] INFO org.star.orderly.producer.DLJDOrderProducer - 当前操作：扣减库存，订单id：2
22:03:43.250 [main] INFO org.star.orderly.producer.DLJDOrderProducer - keys：2，hashCode：50，size：4，index：2，messageQueues：{"body":"5aKe5Yqg56ev5YiG77yM6K6i5Y2VaWTvvJoy","delayTimeLevel":0,"flag":0,"keys":"2","properties":{"KEYS":"2","WAIT":"true","TAGS":"DLJDOrderTag"},"tags":"DLJDOrderTag","topic":"DLJDOrderTopic","waitStoreMsgOK":true}
22:03:43.250 [main] INFO org.star.orderly.producer.DLJDOrderProducer - 当前操作：增加积分，订单id：2
22:03:43.252 [main] INFO org.star.orderly.producer.DLJDOrderProducer - keys：3，hashCode：51，size：4，index：3，messageQueues：{"body":"5Yib5bu66K6i5Y2V77yM6K6i5Y2VaWTvvJoz","delayTimeLevel":0,"flag":0,"keys":"3","properties":{"KEYS":"3","WAIT":"true","TAGS":"DLJDOrderTag"},"tags":"DLJDOrderTag","topic":"DLJDOrderTopic","waitStoreMsgOK":true}
22:03:43.253 [main] INFO org.star.orderly.producer.DLJDOrderProducer - 当前操作：创建订单，订单id：3
22:03:43.256 [main] INFO org.star.orderly.producer.DLJDOrderProducer - keys：3，hashCode：51，size：4，index：3，messageQueues：{"body":"5omj5YeP5bqT5a2Y77yM6K6i5Y2VaWTvvJoz","delayTimeLevel":0,"flag":0,"keys":"3","properties":{"KEYS":"3","WAIT":"true","TAGS":"DLJDOrderTag"},"tags":"DLJDOrderTag","topic":"DLJDOrderTopic","waitStoreMsgOK":true}
22:03:43.256 [main] INFO org.star.orderly.producer.DLJDOrderProducer - 当前操作：扣减库存，订单id：3
22:03:43.259 [main] INFO org.star.orderly.producer.DLJDOrderProducer - keys：3，hashCode：51，size：4，index：3，messageQueues：{"body":"5aKe5Yqg56ev5YiG77yM6K6i5Y2VaWTvvJoz","delayTimeLevel":0,"flag":0,"keys":"3","properties":{"KEYS":"3","WAIT":"true","TAGS":"DLJDOrderTag"},"tags":"DLJDOrderTag","topic":"DLJDOrderTopic","waitStoreMsgOK":true}
22:03:43.259 [main] INFO org.star.orderly.producer.DLJDOrderProducer - 当前操作：增加积分，订单id：3
22:03:43.262 [main] INFO org.star.orderly.producer.DLJDOrderProducer - keys：4，hashCode：52，size：4，index：0，messageQueues：{"body":"5Yib5bu66K6i5Y2V77yM6K6i5Y2VaWTvvJo0","delayTimeLevel":0,"flag":0,"keys":"4","properties":{"KEYS":"4","WAIT":"true","TAGS":"DLJDOrderTag"},"tags":"DLJDOrderTag","topic":"DLJDOrderTopic","waitStoreMsgOK":true}
22:03:43.262 [main] INFO org.star.orderly.producer.DLJDOrderProducer - 当前操作：创建订单，订单id：4
22:03:43.266 [main] INFO org.star.orderly.producer.DLJDOrderProducer - keys：4，hashCode：52，size：4，index：0，messageQueues：{"body":"5omj5YeP5bqT5a2Y77yM6K6i5Y2VaWTvvJo0","delayTimeLevel":0,"flag":0,"keys":"4","properties":{"KEYS":"4","WAIT":"true","TAGS":"DLJDOrderTag"},"tags":"DLJDOrderTag","topic":"DLJDOrderTopic","waitStoreMsgOK":true}
22:03:43.266 [main] INFO org.star.orderly.producer.DLJDOrderProducer - 当前操作：扣减库存，订单id：4
22:03:43.269 [main] INFO org.star.orderly.producer.DLJDOrderProducer - keys：4，hashCode：52，size：4，index：0，messageQueues：{"body":"5aKe5Yqg56ev5YiG77yM6K6i5Y2VaWTvvJo0","delayTimeLevel":0,"flag":0,"keys":"4","properties":{"KEYS":"4","WAIT":"true","TAGS":"DLJDOrderTag"},"tags":"DLJDOrderTag","topic":"DLJDOrderTopic","waitStoreMsgOK":true}
22:03:43.270 [main] INFO org.star.orderly.producer.DLJDOrderProducer - 当前操作：增加积分，订单id：4
22:03:43.272 [main] INFO org.star.orderly.producer.DLJDOrderProducer - keys：5，hashCode：53，size：4，index：1，messageQueues：{"body":"5Yib5bu66K6i5Y2V77yM6K6i5Y2VaWTvvJo1","delayTimeLevel":0,"flag":0,"keys":"5","properties":{"KEYS":"5","WAIT":"true","TAGS":"DLJDOrderTag"},"tags":"DLJDOrderTag","topic":"DLJDOrderTopic","waitStoreMsgOK":true}
22:03:43.273 [main] INFO org.star.orderly.producer.DLJDOrderProducer - 当前操作：创建订单，订单id：5
22:03:43.275 [main] INFO org.star.orderly.producer.DLJDOrderProducer - keys：5，hashCode：53，size：4，index：1，messageQueues：{"body":"5omj5YeP5bqT5a2Y77yM6K6i5Y2VaWTvvJo1","delayTimeLevel":0,"flag":0,"keys":"5","properties":{"KEYS":"5","WAIT":"true","TAGS":"DLJDOrderTag"},"tags":"DLJDOrderTag","topic":"DLJDOrderTopic","waitStoreMsgOK":true}
22:03:43.275 [main] INFO org.star.orderly.producer.DLJDOrderProducer - 当前操作：扣减库存，订单id：5
22:03:43.277 [main] INFO org.star.orderly.producer.DLJDOrderProducer - keys：5，hashCode：53，size：4，index：1，messageQueues：{"body":"5aKe5Yqg56ev5YiG77yM6K6i5Y2VaWTvvJo1","delayTimeLevel":0,"flag":0,"keys":"5","properties":{"KEYS":"5","WAIT":"true","TAGS":"DLJDOrderTag"},"tags":"DLJDOrderTag","topic":"DLJDOrderTopic","waitStoreMsgOK":true}
22:03:43.277 [main] INFO org.star.orderly.producer.DLJDOrderProducer - 当前操作：增加积分，订单id：5
22:03:43.280 [main] INFO org.star.orderly.producer.DLJDOrderProducer - keys：6，hashCode：54，size：4，index：2，messageQueues：{"body":"5Yib5bu66K6i5Y2V77yM6K6i5Y2VaWTvvJo2","delayTimeLevel":0,"flag":0,"keys":"6","properties":{"KEYS":"6","WAIT":"true","TAGS":"DLJDOrderTag"},"tags":"DLJDOrderTag","topic":"DLJDOrderTopic","waitStoreMsgOK":true}
22:03:43.280 [main] INFO org.star.orderly.producer.DLJDOrderProducer - 当前操作：创建订单，订单id：6
22:03:43.284 [main] INFO org.star.orderly.producer.DLJDOrderProducer - keys：6，hashCode：54，size：4，index：2，messageQueues：{"body":"5omj5YeP5bqT5a2Y77yM6K6i5Y2VaWTvvJo2","delayTimeLevel":0,"flag":0,"keys":"6","properties":{"KEYS":"6","WAIT":"true","TAGS":"DLJDOrderTag"},"tags":"DLJDOrderTag","topic":"DLJDOrderTopic","waitStoreMsgOK":true}
22:03:43.284 [main] INFO org.star.orderly.producer.DLJDOrderProducer - 当前操作：扣减库存，订单id：6
22:03:43.288 [main] INFO org.star.orderly.producer.DLJDOrderProducer - keys：6，hashCode：54，size：4，index：2，messageQueues：{"body":"5aKe5Yqg56ev5YiG77yM6K6i5Y2VaWTvvJo2","delayTimeLevel":0,"flag":0,"keys":"6","properties":{"KEYS":"6","WAIT":"true","TAGS":"DLJDOrderTag"},"tags":"DLJDOrderTag","topic":"DLJDOrderTopic","waitStoreMsgOK":true}
22:03:43.288 [main] INFO org.star.orderly.producer.DLJDOrderProducer - 当前操作：增加积分，订单id：6
22:03:43.291 [main] INFO org.star.orderly.producer.DLJDOrderProducer - DLJDOrderProducer start success# 消费者1
22:03:43.237 [ConsumeMessageThread_12] INFO org.star.orderly.consumer.DLJDOrderConsumer1 - 我是消费者DLJDOrderConsumer1，当前线程：ConsumeMessageThread_12，队列ID：1，收到消息：创建订单，订单id：1
22:03:43.240 [ConsumeMessageThread_13] INFO org.star.orderly.consumer.DLJDOrderConsumer1 - 我是消费者DLJDOrderConsumer1，当前线程：ConsumeMessageThread_13，队列ID：1，收到消息：扣减库存，订单id：1
22:03:43.245 [ConsumeMessageThread_14] INFO org.star.orderly.consumer.DLJDOrderConsumer1 - 我是消费者DLJDOrderConsumer1，当前线程：ConsumeMessageThread_14，队列ID：1，收到消息：增加积分，订单id：1
22:03:43.266 [ConsumeMessageThread_15] INFO org.star.orderly.consumer.DLJDOrderConsumer1 - 我是消费者DLJDOrderConsumer1，当前线程：ConsumeMessageThread_15，队列ID：0，收到消息：创建订单，订单id：4
22:03:43.271 [ConsumeMessageThread_16] INFO org.star.orderly.consumer.DLJDOrderConsumer1 - 我是消费者DLJDOrderConsumer1，当前线程：ConsumeMessageThread_16，队列ID：0，收到消息：扣减库存，订单id：4
22:03:43.273 [ConsumeMessageThread_17] INFO org.star.orderly.consumer.DLJDOrderConsumer1 - 我是消费者DLJDOrderConsumer1，当前线程：ConsumeMessageThread_17，队列ID：0，收到消息：增加积分，订单id：4
22:03:43.277 [ConsumeMessageThread_18] INFO org.star.orderly.consumer.DLJDOrderConsumer1 - 我是消费者DLJDOrderConsumer1，当前线程：ConsumeMessageThread_18，队列ID：1，收到消息：创建订单，订单id：5
22:03:43.279 [ConsumeMessageThread_19] INFO org.star.orderly.consumer.DLJDOrderConsumer1 - 我是消费者DLJDOrderConsumer1，当前线程：ConsumeMessageThread_19，队列ID：1，收到消息：扣减库存，订单id：5
22:03:43.281 [ConsumeMessageThread_20] INFO org.star.orderly.consumer.DLJDOrderConsumer1 - 我是消费者DLJDOrderConsumer1，当前线程：ConsumeMessageThread_20，队列ID：1，收到消息：增加积分，订单id：5# 消费者2
22:03:43.272 [ConsumeMessageThread_2] INFO org.star.orderly.consumer.DLJDOrderConsumer2 - 我是消费者DLJDOrderConsumer2，当前线程：ConsumeMessageThread_2，队列ID：3，收到消息：创建订单，订单id：3
22:03:43.272 [ConsumeMessageThread_1] INFO org.star.orderly.consumer.DLJDOrderConsumer2 - 我是消费者DLJDOrderConsumer2，当前线程：ConsumeMessageThread_1，队列ID：2，收到消息：创建订单，订单id：2
22:03:43.275 [ConsumeMessageThread_1] INFO org.star.orderly.consumer.DLJDOrderConsumer2 - 我是消费者DLJDOrderConsumer2，当前线程：ConsumeMessageThread_1，队列ID：2，收到消息：扣减库存，订单id：2
22:03:43.275 [ConsumeMessageThread_2] INFO org.star.orderly.consumer.DLJDOrderConsumer2 - 我是消费者DLJDOrderConsumer2，当前线程：ConsumeMessageThread_2，队列ID：3，收到消息：扣减库存，订单id：3
22:03:43.275 [ConsumeMessageThread_1] INFO org.star.orderly.consumer.DLJDOrderConsumer2 - 我是消费者DLJDOrderConsumer2，当前线程：ConsumeMessageThread_1，队列ID：2，收到消息：增加积分，订单id：2
22:03:43.275 [ConsumeMessageThread_2] INFO org.star.orderly.consumer.DLJDOrderConsumer2 - 我是消费者DLJDOrderConsumer2，当前线程：ConsumeMessageThread_2，队列ID：3，收到消息：增加积分，订单id：3
22:03:43.287 [ConsumeMessageThread_3] INFO org.star.orderly.consumer.DLJDOrderConsumer2 - 我是消费者DLJDOrderConsumer2，当前线程：ConsumeMessageThread_3，队列ID：2，收到消息：创建订单，订单id：6
22:03:43.299 [ConsumeMessageThread_4] INFO org.star.orderly.consumer.DLJDOrderConsumer2 - 我是消费者DLJDOrderConsumer2，当前线程：ConsumeMessageThread_4，队列ID：2，收到消息：扣减库存，订单id：6
22:03:43.303 [ConsumeMessageThread_5] INFO org.star.orderly.consumer.DLJDOrderConsumer2 - 我是消费者DLJDOrderConsumer2，当前线程：ConsumeMessageThread_5，队列ID：2，收到消息：增加积分，订单id：6

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