From 9ddd162d2584f39c8e3b303db91dc43143381ecc Mon Sep 17 00:00:00 2001
From: gtully <gary.tully@gmail.com>
Date: Thu, 22 Oct 2015 15:49:44 +0100
Subject: [PATCH] https://issues.apache.org/jira/browse/AMQ-4361 - implement
 suggestion from Sam hendley with thanks, avoid the
 IllegalMonitorStateException

---
 .../src/main/java/org/apache/activemq/usage/MemoryUsage.java    | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/activemq-client/src/main/java/org/apache/activemq/usage/MemoryUsage.java b/activemq-client/src/main/java/org/apache/activemq/usage/MemoryUsage.java
index 74fb5c38a8..8c38c2dc02 100755
--- a/activemq-client/src/main/java/org/apache/activemq/usage/MemoryUsage.java
+++ b/activemq-client/src/main/java/org/apache/activemq/usage/MemoryUsage.java
@@ -74,9 +74,9 @@ public class MemoryUsage extends Usage<MemoryUsage> {
                     while (percentUsage >= 100 && isStarted()) {
                         waitForSpaceCondition.await();
                     }
-                    usageLock.readLock().lock();
                 } finally {
                     usageLock.writeLock().unlock();
+                    usageLock.readLock().lock();
                 }
             }