Spring JmsTemplate's Daemon threads that stay alive after stopping tomcat application

Question

I am sending a message to IBM WebSphere MQ(the mq jar version is 7.0.1.9 and javax.jms is 1.1) using a Spring JmsTemplate class from my web application.

The connectionFactory i am using is MQQueueConnectionFactory.

The following daemon threads are created on executing send() on JmsTempalte and on instantiating MQQueueConnectionFactory.

PROBLEM

I am getting a message on tomcat command line showing these three threads as memory leaks when i stop the web application in the tomcat admin page. The daemon threads are

FROM JCONSOLE

THREAD 1

Name: JMSCCThreadPoolMaster State: WAITING on java.lang.Object@9f6e3e9 Total blocked: 3 Total waited: 4

Stack trace: java.lang.Object.wait(Native Method) java.lang.Object.wait(Object.java:485) com.ibm.msg.client.commonservices.j2se.workqueue.WorkQueueManagerImplementation$WorkQueueManagerThread.waitForNotification(WorkQueueManagerImplementation.java:651) com.ibm.msg.client.commonservices.j2se.workqueue.WorkQueueManagerImplementation$WorkQueueManagerThread.waitForNotification(WorkQueueManagerImplementation.java:621) com.ibm.msg.client.commonservices.j2se.workqueue.WorkQueueManagerImplementation$WorkQueueManagerThread.run(WorkQueueManagerImplementation.java:887)

THREAD 2

Name: JMSCCThreadPoolWorker-2 State: WAITING on com.ibm.mq.jmqi.remote.internal.RemoteReconnectThread$ReconnectMutex@3d3c3e45 Total blocked: 0 Total waited: 1

Stack trace: java.lang.Object.wait(Native Method) java.lang.Object.wait(Object.java:485) com.ibm.mq.jmqi.remote.internal.RemoteReconnectThread.bestHconn(RemoteReconnectThread.java:672) com.ibm.mq.jmqi.remote.internal.RemoteReconnectThread.run(RemoteReconnectThread.java:129) com.ibm.msg.client.commonservices.workqueue.WorkQueueItem.runTask(WorkQueueItem.java:209) com.ibm.msg.client.commonservices.workqueue.SimpleWorkQueueItem.runItem(SimpleWorkQueueItem.java:100) com.ibm.msg.client.commonservices.workqueue.WorkQueueItem.run(WorkQueueItem.java:224) com.ibm.msg.client.commonservices.workqueue.WorkQueueManager.runWorkQueueItem(WorkQueueManager.java:298) com.ibm.msg.client.commonservices.j2se.workqueue.WorkQueueManagerImplementation$ThreadPoolWorker.run(WorkQueueManagerImplementation.java:1220)

THREAD 3 (Dies after a min)

THIS ONE is created on instantiation of MQQueueConnectionFactory

Name: WebSphere MQ Trace Monitor State: TIMED_WAITING Total blocked: 0 Total waited: 5

Stack trace: java.lang.Thread.sleep(Native Method) com.ibm.mq.commonservices.internal.monitor.TraceMonitor.run(TraceMonitor.java:134)

How to make sure these daemon threads die.

Answer 1

my Spring context was not closing properly and the JMS Connection factory was being managed by my spring container therefore it caused the leak.

Answer 2

I believe that problem is within WMQ client jars and not within spring. Remove client jars from application and provide them at higher classloader level like coping them within tomcat/lib folder. This will not solve the problem, but work around it, as all applications will share common base and no leak will happen on application restart.