From 2c5c2bda1f770e30d332b510987675073524c415 Mon Sep 17 00:00:00 2001
From: itxaiohanglover <1531137510@qq.com>
Date: Sun, 5 Jul 2026 17:21:48 +0800
Subject: [PATCH] [ISSUE #411] Fix NPE when getAllSubscriptionGroup returns
 null

When mqAdminExt.getAllSubscriptionGroup() returns null (e.g. broker
not reachable or ACL denied), the code calls
subscriptionGroupWrapper.getSubscriptionGroupTable() which throws NPE.

Add null check after getAllSubscriptionGroup call, skip to next broker
if null. Also fix post-loop check to handle null (empty broker table).
---
 .../dashboard/service/impl/ConsumerServiceImpl.java         | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/main/java/org/apache/rocketmq/dashboard/service/impl/ConsumerServiceImpl.java b/src/main/java/org/apache/rocketmq/dashboard/service/impl/ConsumerServiceImpl.java
index 58fb5f5d..6d5eef80 100644
--- a/src/main/java/org/apache/rocketmq/dashboard/service/impl/ConsumerServiceImpl.java
+++ b/src/main/java/org/apache/rocketmq/dashboard/service/impl/ConsumerServiceImpl.java
@@ -180,6 +180,10 @@ public void makeGroupListCache(String address) {
             ClusterInfo clusterInfo = clusterInfoService.get();
             for (BrokerData brokerData : clusterInfo.getBrokerAddrTable().values()) {
                 subscriptionGroupWrapper = mqAdminExt.getAllSubscriptionGroup(brokerData.selectBrokerAddr(), 30000L);
+                if (subscriptionGroupWrapper == null) {
+                    logger.warn("getAllSubscriptionGroup returned null for broker: {}", brokerData.selectBrokerAddr());
+                    continue;
+                }
                 for (String groupName : subscriptionGroupWrapper.getSubscriptionGroupTable().keySet()) {
                     if (!consumerGroupMap.containsKey(groupName)) {
                         consumerGroupMap.putIfAbsent(groupName, new ArrayList<>());
@@ -194,7 +198,7 @@ public void makeGroupListCache(String address) {
             throw new RuntimeException(err);
         }
 
-        if (subscriptionGroupWrapper != null && subscriptionGroupWrapper.getSubscriptionGroupTable().isEmpty()) {
+        if (subscriptionGroupWrapper == null || subscriptionGroupWrapper.getSubscriptionGroupTable().isEmpty()) {
             logger.warn("No subscription group information available");
             isCacheBeingBuilt = false;
             return;