Expose current cached session count

Closes gh-26811

spring-jms/src/main/java/org/springframework/jms/connection/CachingConnectionFactory.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2020 the original author or authors.
+ * Copyright 2002-2021 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -179,6 +179,23 @@ public boolean isCacheConsumers() {
  }
 
 
+ /**
+ * Return a current session count, indicating the number of sessions currently
+ * cached by this connection factory.
+ * @since 5.3.7
+ */
+ public int getCachedSessionCount() {
+ int count = 0;
+ synchronized (this.cachedSessions) {
+ for (Deque<Session> sessionList : this.cachedSessions.values()) {
+ synchronized (sessionList) {
+ count += sessionList.size();
+ }
+ }
+ }
+ return count;
+ }
+
  /**
  * Resets the Session cache as well.
  */