From f9d51989a88bd4da646f825338ea25399d43311f Mon Sep 17 00:00:00 2001
From: Gary Russell <grussell@pivotal.io>
Date: Thu, 22 Mar 2018 15:10:13 -0400
Subject: [PATCH] INT-4441: Fix ACMH Concurrency Problem

JIRA: https://jira.spring.io/browse/INT-4441

Possible concurrent updates to `AbstractCorrelatingMessageHandler.groupIds` and
`expireGroupScheduledFutures`.
---
 .../aggregator/AbstractCorrelatingMessageHandler.java      | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/spring-integration-core/src/main/java/org/springframework/integration/aggregator/AbstractCorrelatingMessageHandler.java b/spring-integration-core/src/main/java/org/springframework/integration/aggregator/AbstractCorrelatingMessageHandler.java
index f4e4f15589..8ff9370bb4 100644
--- a/spring-integration-core/src/main/java/org/springframework/integration/aggregator/AbstractCorrelatingMessageHandler.java
+++ b/spring-integration-core/src/main/java/org/springframework/integration/aggregator/AbstractCorrelatingMessageHandler.java
@@ -20,12 +20,11 @@ import java.util.Collection;
 import java.util.Collections;
 import java.util.Comparator;
 import java.util.Date;
-import java.util.HashMap;
-import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
 import java.util.UUID;
+import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.ScheduledFuture;
 import java.util.concurrent.locks.Lock;
 
@@ -98,9 +97,9 @@ public abstract class AbstractCorrelatingMessageHandler extends AbstractMessageP
 
 	private final Comparator<Message<?>> sequenceNumberComparator = new MessageSequenceComparator();
 
-	private final Map<UUID, ScheduledFuture<?>> expireGroupScheduledFutures = new HashMap<>();
+	private final Map<UUID, ScheduledFuture<?>> expireGroupScheduledFutures = new ConcurrentHashMap<>();
 
-	private final Set<Object> groupIds =  new HashSet<>();
+	private final Set<Object> groupIds =  ConcurrentHashMap.newKeySet();
 
 	private MessageGroupProcessor outputProcessor;