From 65a22e5e809ecbd20b3475cd8644fdf7aa5e8490 Mon Sep 17 00:00:00 2001
From: Hirotaka Ikoma <hikoma@gmail.com>
Date: Thu, 27 Feb 2020 00:38:50 +0900
Subject: [PATCH] Fix NPE in HouseKeeper.stopScavenging (#4604)

* Fix NPE in HouseKeeper.stopScavenging

Signed-off-by: Hirotaka Ikoma <hikoma@gmail.com>
---
 .../java/org/eclipse/jetty/server/session/HouseKeeper.java     | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/jetty-server/src/main/java/org/eclipse/jetty/server/session/HouseKeeper.java b/jetty-server/src/main/java/org/eclipse/jetty/server/session/HouseKeeper.java
index 670957caf24..17616b8c0a5 100644
--- a/jetty-server/src/main/java/org/eclipse/jetty/server/session/HouseKeeper.java
+++ b/jetty-server/src/main/java/org/eclipse/jetty/server/session/HouseKeeper.java
@@ -158,8 +158,9 @@ public class HouseKeeper extends AbstractLifeCycle
                 LOG.info("{} Stopped scavenging", _sessionIdManager.getWorkerName());
             }
             _task = null;
-            if (_ownScheduler)
+            if (_ownScheduler && _scheduler != null)
             {
+                _ownScheduler = false;
                 _scheduler.stop();
                 _scheduler = null;
             }