From 01cef910dbde1e8fe2fa977f982d7d1aa407a895 Mon Sep 17 00:00:00 2001
From: Robert Davies <rajdavies@apache.org>
Date: Mon, 21 Jan 2008 13:09:38 +0000
Subject: [PATCH] Fix for https://issues.apache.org/activemq/browse/AMQ-1560

git-svn-id: https://svn.apache.org/repos/asf/activemq/trunk@613874 13f79535-47bb-0310-9956-ffa450edef68
---
 .../activemq/store/kahadaptor/KahaTopicReferenceStore.java      | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/activemq-core/src/main/java/org/apache/activemq/store/kahadaptor/KahaTopicReferenceStore.java b/activemq-core/src/main/java/org/apache/activemq/store/kahadaptor/KahaTopicReferenceStore.java
index a3b8994645..f490bf95a6 100644
--- a/activemq-core/src/main/java/org/apache/activemq/store/kahadaptor/KahaTopicReferenceStore.java
+++ b/activemq-core/src/main/java/org/apache/activemq/store/kahadaptor/KahaTopicReferenceStore.java
@@ -70,7 +70,7 @@ public class KahaTopicReferenceStore extends KahaReferenceStore implements Topic
         throw new RuntimeException("Use addMessageReference instead");
     }
 
-    public void addMessageReference(final ConnectionContext context, final MessageId messageId,
+    public synchronized void addMessageReference(final ConnectionContext context, final MessageId messageId,
                                     final ReferenceData data) {
         final ReferenceRecord record = new ReferenceRecord(messageId.toString(), data);
         final int subscriberCount = subscriberMessages.size();