[jboss-jira] [JBoss JIRA] Created: (JBAS-7559) Unable to add RMINotificationListener for "JMImplementation:type=MBeanServerDelegate" from different VM

[martin walla (JIRA)]

Unable to add RMINotificationListener for "JMImplementation:type=MBeanServerDelegate" from different VM
-------------------------------------------------------------------------------------------------------

                 Key: JBAS-7559
                 URL: https://jira.jboss.org/jira/browse/JBAS-7559
             Project: JBoss Application Server
          Issue Type: Bug
      Security Level: Public (Everyone can see)
          Components: JMX
    Affects Versions: JBossAS-5.1.0.GA
         Environment: Windows XP, JBoss 5.1.0.GA, JDK 1.6.0_16
            Reporter: martin walla
            Assignee: Dimitris Andreadis


I listen for the Notifications (JMX.mbean.registered, JMX.mbean.unregistered) of the MBeanServer "JMImplementation:type=MBeanServerDelegate".
I want to do that inside the JBoss VM and also from a different VM (e.g. a JUnit Test case).
I add a RMINotificationListener via the RMIAdaptor.

If i do it within the JBoss VM everything is fine and works OK.

If i do it from a different VM the RMINotificationListener class can't be found.

org.jboss.invocation.JBossLazyUnmarshallingException: getArguments failed
	at org.jboss.invocation.MarshalledInvocation.getArguments(MarshalledInvocation.java:513)
	at org.jboss.jmx.connector.invoker.InvokerAdaptorService.invoke(InvokerAdaptorService.java:233)
Caused by: java.lang.ClassNotFoundException: org.jboss.jmx.adaptor.rmi.RMINotificationListener
	at java.net.URLClassLoader$1.run(URLClassLoader.java:200)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
	at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:252)
	at org.jboss.invocation.MarshalledValueInputStream.resolveProxyClass(MarshalledValueInputStream.java:159)
	at java.io.ObjectInputStream.readProxyDesc(ObjectInputStream.java:1531)
	at java.io.ObjectInputStream.readClassDesc(ObjectInputStream.java:1493)
	at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1732)
	at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1329)
	at java.io.ObjectInputStream.readArray(ObjectInputStream.java:1667)
	at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1323)
	at java.io.ObjectInputStream.readObject(ObjectInputStream.java:351)
	at org.jboss.invocation.MarshalledValue.get(MarshalledValue.java:91)
	at org.jboss.invocation.MarshalledInvocation.getArguments(MarshalledInvocation.java:509)
	
The reason is:
In case of calling addNotificationListener() from a different VM the invocation is a MarshalledInvocation.
In the invoke() method of the org.jboss.jmx.connector.invoker.InvokerAdaptorService  there is a call to
            Object[] args = invocation.getArguments();

In the getArguments() it comes to the unmarshalling of the arguments (one is the RMINotificationListener).
Therefore it is tried to load the argument classes via the Thread's contextClassLoader.

In the InvokerAdaptorService few statements before the getArguments() call there is a call to
getClassLoaderFor(ObjectName name) of the MBeanServerImpl
            // Obtain the ClassLoader associated with the MBean deployment
            newCL = server.getClassLoaderFor(objectName);

The InvokerAdaptorService then sets the Thread's contextClassLoader.
         if (newCL != null && newCL != oldCL)
            SecurityActions.setContextClassLoader(newCL);


In the method getClassLoaderFor() the SystemClassLoader is returned for the "JMImplementation:type=MBeanServerDelegate".

   public ClassLoader getClassLoaderFor(ObjectName name)
           throws InstanceNotFoundException
   {
      MBeanEntry entry = registry.get(name);
      checkMBeanPermission(entry.getResourceClassName(), null, name,
         "getClassLoaderFor");
      
      ClassLoader cl = entry.getClassLoader();
      if (cl == null)
         cl = entry.getResourceInstance().getClass().getClassLoader();
      if (cl == null)
         cl = ClassLoader.getSystemClassLoader();
      return cl;
   }

The SystemClassLoader didn't the see RMINotificationListener.

Possible solution:
If null or the Thread's contextClassLoader would be returned instead of the SystemClassLoader then the InvokerAdaptorService
didn't modify the Thread's contextClassLoader and the RMINotificationListener is found (and it works OK).


-- 
This message is automatically generated by JIRA.
-
If you think it was sent incorrectly contact one of the administrators: https://jira.jboss.org/jira/secure/Administrators.jspa
-
For more information on JIRA, see: http://www.atlassian.com/software/jira