From 5b23f73bc0d4c8943ad00d261a759a4040e55278 Mon Sep 17 00:00:00 2001
From: markpollack <mark.pollack@springsource.com>
Date: Fri, 24 Oct 2008 14:18:35 +0000
Subject: [PATCH] SPRNET-1070 - SimpleMessageListenerContainer to check for
 null sessions and consumers when shutting down.

---
 .../SimpleMessageListenerContainer.cs         | 29 ++++++++++++-------
 1 file changed, 19 insertions(+), 10 deletions(-)

diff --git a/src/Spring/Spring.Messaging.Nms/Messaging/Nms/Listener/SimpleMessageListenerContainer.cs b/src/Spring/Spring.Messaging.Nms/Messaging/Nms/Listener/SimpleMessageListenerContainer.cs
index e9504f51..296b35fa 100644
--- a/src/Spring/Spring.Messaging.Nms/Messaging/Nms/Listener/SimpleMessageListenerContainer.cs
+++ b/src/Spring/Spring.Messaging.Nms/Messaging/Nms/Listener/SimpleMessageListenerContainer.cs
@@ -323,18 +323,27 @@ namespace Spring.Messaging.Nms.Listener
         /// <throws>NMSException if destruction failed </throws>
         protected override void DoShutdown()
         {
-            logger.Debug("Closing NMS MessageConsumers");
-            foreach (IMessageConsumer messageConsumer in consumers)
+            lock (consumersMonitor)
             {
-                NmsUtils.CloseMessageConsumer(messageConsumer);
+                if (consumers != null)
+                {
+                    logger.Debug("Closing NMS MessageConsumers");
+                    foreach (IMessageConsumer messageConsumer in consumers)
+                    {
+                        NmsUtils.CloseMessageConsumer(messageConsumer);
+                    }
+                }
+                if (sessions != null)
+                {
+                    logger.Debug("Closing NMS Sessions");
+                    foreach (ISession session in sessions)
+                    {
+                        NmsUtils.CloseSession(session);
+                    }
+                }
+                consumers = null;
+                sessions = null;
             }
-            logger.Debug("Closing NMS Sessions");
-            foreach (ISession session in sessions)
-            {
-                NmsUtils.CloseSession(session);
-            }
-            consumers = null;
-            sessions = null;
         }