From 44c31a6aad26ce2a4e7225e93e6fb26612f07b2c Mon Sep 17 00:00:00 2001
From: Bao Tran <tran.bao51093@gmail.com>
Date: Sun, 14 May 2017 18:55:53 +0300
Subject: [PATCH] Fix duplicate STOMP subscription id issue

Issue: SPR-15543
---
 .../messaging/simp/broker/DefaultSubscriptionRegistry.java | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/spring-messaging/src/main/java/org/springframework/messaging/simp/broker/DefaultSubscriptionRegistry.java b/spring-messaging/src/main/java/org/springframework/messaging/simp/broker/DefaultSubscriptionRegistry.java
index 92694f8d9a9..501f8c9f396 100644
--- a/spring-messaging/src/main/java/org/springframework/messaging/simp/broker/DefaultSubscriptionRegistry.java
+++ b/spring-messaging/src/main/java/org/springframework/messaging/simp/broker/DefaultSubscriptionRegistry.java
@@ -292,8 +292,11 @@ public class DefaultSubscriptionRegistry extends AbstractSubscriptionRegistry {
 					String cachedDestination = entry.getKey();
 					if (getPathMatcher().match(destination, cachedDestination)) {
 						LinkedMultiValueMap<String, String> subs = entry.getValue();
-						subs.add(sessionId, subsId);
-						this.accessCache.put(cachedDestination, subs.deepCopy());
+						// Subscription id's may also be populated via getSubscriptions()
+						if (!subs.containsKey(sessionId) || !subs.get(sessionId).contains(subsId)) {
+							subs.add(sessionId, subsId);
+							this.accessCache.put(cachedDestination, subs.deepCopy());
+						}
 					}
 				}
 			}