diff --git a/src/main/java/com/njcn/middle/rocket/domain/BaseMessage.java b/src/main/java/com/njcn/middle/rocket/domain/BaseMessage.java
index b83d893..d50e9f0 100644
--- a/src/main/java/com/njcn/middle/rocket/domain/BaseMessage.java
+++ b/src/main/java/com/njcn/middle/rocket/domain/BaseMessage.java
@@ -15,6 +15,7 @@ public abstract class BaseMessage {
 
     /**
      * 业务键，用于RocketMQ控制台查看消费情况
+     * 为了保证唯一性，使用雪花算法生成一个随机id
      */
     protected String key = IdUtil.getSnowflake().nextIdStr();