question on tomcat and jmx

Question

What is the MBeanServerFactory.findMBeanServer(null); exactly doing?
Returns a list of all registered MBeanServers? Registered where?
I am asking because I have the following problem.
I have a java web app deployed in Tomcat using a service wrapper.
I have custom connector implementations in my server.xml that use ManagedBeans (spring enabled).
If I start the app via the service wrapper all is ok.
If I start the web app through Tomcat directly it seems that the deployment breaks.
All I see in the logs is that the connector does a

MBeanServerFactory.findMBeanServer(null);

and then tries to invoke the bean beanServer.invoke(name, operationName, null, null);
The result is a InstanceNotFoundException.
It seems that the managed beans are not loaded in case I do not use a service wrapper? Is my understanding correct? Any input on how to debug this issue is highly welcome!

Answer 1

The javadoc says that when you pass null , it returns the servers registered in the current JVM. If you are using JSW, then you cannot use null as JSW forks the VM as a separate process. This is why you see the InstanceNotFoundException .