diff --git a/src/main/java/com/upchina/group/service/common/GroupMessageService.java b/src/main/java/com/upchina/group/service/common/GroupMessageService.java
index 033a670..b179af1 100644
--- a/src/main/java/com/upchina/group/service/common/GroupMessageService.java
+++ b/src/main/java/com/upchina/group/service/common/GroupMessageService.java
@@ -65,11 +65,17 @@ public class GroupMessageService {
      */
     @PostConstruct
     private void initVideoTopic() {
+        // 后端群组消息 /admin/group/topic/{groupId}
         adminGroupTopic = initTopic(CacheKey.GroupMessageTopicKey.ADMIN_GROUP_TOPIC, ADMIN_GROUP_TOPIC, true, false, false);
-        adminPrivateTopic = initTopic(CacheKey.GroupMessageTopicKey.ADMIN_PRIVATE_TOPIC, ADMIN_PRIVATE_TOPIC, true, true, false);
+        // 后端私聊消息 /admin/private/topic/{groupId}
+        adminPrivateTopic = initTopic(CacheKey.GroupMessageTopicKey.ADMIN_PRIVATE_TOPIC, ADMIN_PRIVATE_TOPIC, true, false, false);
+        // 后端会话消息 /admin/session/topic/{userId}/{sessionId}
         adminSessionTopic = initTopic(CacheKey.GroupMessageTopicKey.ADMIN_SESSION_TOPIC, ADMIN_SESSION_TOPIC, false, true, true);
+        // APP端群组消息 /app/group/topic/{groupId}
         appGroupTopic = initTopic(CacheKey.GroupMessageTopicKey.APP_GROUP_TOPIC, APP_GROUP_TOPIC, true, false, false);
+        // APP端私聊消息 /app/private/topic/{groupId}/{userId}
         appPrivateTopic = initTopic(CacheKey.GroupMessageTopicKey.APP_PRIVATE_TOPIC, APP_PRIVATE_TOPIC, true, true, false);
+        // APP端会话消息 /app/session/topic/{userId}/{sessionId}
         appSessionTopic = initTopic(CacheKey.GroupMessageTopicKey.APP_SESSION_TOPIC, APP_SESSION_TOPIC, false, true, true);
     }