+++ This bug was initially created as a clone of Bug #970177 +++

Description of problem:
Cannot browse the GUI if the plugin scan task does not execute quickly.

Version-Release number of selected component (if applicable):
4.7

How reproducible:
Always

Steps to Reproduce:
1.Upload a new (version of a) plugin with various resource types (ie as7 plugin)
2.Wait for the plugin scan task to start (look at the server logs)
3.While the server is updating resource types, try to browse the GUI

Actual results:
Cannot browse the GUI and the server logs shows the attached stack trace

Expected results:
Can browse the GUI

Additional info:
The plugin scan is currently triggered with an EJB timer in a @Singleton bean (org.rhq.enterprise.server.core.StartupBean). Those beans by default have container managed concurrency. Without any annotations, the container serializes calls to the bean. So the AuthenticationFilter timeouts on its try to call org.rhq.enterprise.server.core.StartupLocal#isInitialized

--- Additional comment from Thomas Segismont on 2013-06-03 17:58:24 CEST ---

Comments from IRC

<mazz> BTW, there are other @Singleton SLSBs we should examine for this same kind of thing
<mazz> I see two that we should look at
<mazz> org.rhq.enterprise.server.cassandra.SessionManagerBean
<mazz> (that's something jsanda put together for the storage stuff)
<mazz> and org.rhq.enterprise.server.auth.prefs.SubjectPreferencesCacheBean

--- Additional comment from John Mazzitelli on 2013-06-03 18:06:44 CEST ---

(In reply to Thomas Segismont from comment #1)
> <mazz> BTW, there are other @Singleton SLSBs we should examine for this same
> kind of thing
> <mazz> and org.rhq.enterprise.server.auth.prefs.SubjectPreferencesCacheBean

That SubjectPreferencesCacheBean is OK - I remember doing this. Its explicitly marked as CONTAINER and we use the EJB LOCK annotations to ensure we have read/write locking around the appropriate places.

We should ask John S. just to confirm that SessionManagerBean is OK.