From ac760635f600d92d2757383ddd64c116bdf2d4a9 Mon Sep 17 00:00:00 2001
From: Martijn van Groningen <martijn.v.groningen@gmail.com>
Date: Thu, 7 Oct 2021 16:28:11 +0200
Subject: [PATCH] Fix a potential NPE in DataStreamAlias#toString() (#78399)
 (#78461)

Co-authored-by: Elastic Machine <elasticmachine@users.noreply.github.com>
---
 .../org/elasticsearch/cluster/metadata/DataStreamAlias.java     | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/server/src/main/java/org/elasticsearch/cluster/metadata/DataStreamAlias.java b/server/src/main/java/org/elasticsearch/cluster/metadata/DataStreamAlias.java
index 4279b405d117f..9a3fb57cdc656 100644
--- a/server/src/main/java/org/elasticsearch/cluster/metadata/DataStreamAlias.java
+++ b/server/src/main/java/org/elasticsearch/cluster/metadata/DataStreamAlias.java
@@ -332,7 +332,7 @@ public String toString() {
             "name='" + name + '\'' +
             ", dataStreams=" + dataStreams +
             ", writeDataStream='" + writeDataStream + '\'' +
-            ", filter=" + filter.string() +
+            ", filter=" + (filter != null ? filter.string() : "null") +
             '}';
     }
 }