From 66389648d8d6f30555dde429268b9a1ceceda75b Mon Sep 17 00:00:00 2001
From: Julien Nioche <julien@digitalpebble.com>
Date: Sat, 28 Mar 2026 06:44:10 +0000
Subject: [PATCH] Fix NPE in getSupervisorPageInfo for unknown hostnames

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
---
 .../src/main/java/org/apache/storm/daemon/nimbus/Nimbus.java   | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/storm-server/src/main/java/org/apache/storm/daemon/nimbus/Nimbus.java b/storm-server/src/main/java/org/apache/storm/daemon/nimbus/Nimbus.java
index 18c5e5bdf47..36baf6c980e 100644
--- a/storm-server/src/main/java/org/apache/storm/daemon/nimbus/Nimbus.java
+++ b/storm-server/src/main/java/org/apache/storm/daemon/nimbus/Nimbus.java
@@ -4643,6 +4643,9 @@ public SupervisorPageInfo getSupervisorPageInfo(String superId, String host, boo
             } else {
                 supervisorIds = Arrays.asList(superId);
             }
+            if (supervisorIds == null) {
+                supervisorIds = Collections.emptyList();
+            }
             SupervisorPageInfo pageInfo = new SupervisorPageInfo();
             Map<String, Assignment> topoToAssignment = state.assignmentsInfo();
             for (String sid : supervisorIds) {