顺序消费

whatsmars-mq/src/main/java/com/itlong/whatsmars/mq/rocketmq/ordermessage/Producer.java

@@ -24,6 +24,7 @@ public class Producer {
                 Message msg =
                     new Message("TopicTest", tags[i % tags.length], "KEY" + i,
                         ("Hello RocketMQ " + i).getBytes(RemotingHelper.DEFAULT_CHARSET));
+                // 需要顺序消费的消息发往同一队列，比如同一订单号相关的几条需要顺序消费的消息发往同一队列
                 SendResult sendResult = producer.send(msg, new MessageQueueSelector() {
                     @Override
                     public MessageQueue select(List<MessageQueue> mqs, Message msg, Object arg) {