> 1. I have a classloader scanning strategy written and 
> apparently working, however it is rather slow at least in 
> geronimo.  Is anyone interested in it, seeing as how its not 
> an appropriate approach in a app server according to 
> Patrick's comment below?  I think it might still be useful as 
> a "last resort" strategy.

Can you describe it in more detail?

> 2. It looks like the best strategy for geronimo to follow is 
> to figure out which jars in an ee app can possibly have 
> persistent classes in them and supply a list of those jars to 
> the PersistenceUnitInfo.  IIUC scanning those jars is already 
> implemented.

Yes. The easy way to do this is to just include all the jars in the
scope of a given PU (all the jars in the EAR for EAR-scoped; all the
jars in the WAR or EJB-JAR otherwise) in the PUInfo.

-Patrick

-- 
Patrick Linskey
BEA Systems, Inc.
_______________________________________________________________________
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> -----Original Message-----
> From: David Jencks [mailto:[EMAIL PROTECTED] 
> Sent: Thursday, April 26, 2007 1:50 PM
> To: open-jpa-dev@incubator.apache.org
> Subject: Re: More questions on runtime schema generation
> 
> Thanks for all the comments, I've learned a lot.
> 
> 1. I have a classloader scanning strategy written and 
> apparently working, however it is rather slow at least in 
> geronimo.  Is anyone interested in it, seeing as how its not 
> an appropriate approach in a app server according to 
> Patrick's comment below?  I think it might still be useful as 
> a "last resort" strategy.
> 
> 2. It looks like the best strategy for geronimo to follow is 
> to figure out which jars in an ee app can possibly have 
> persistent classes in them and supply a list of those jars to 
> the PersistenceUnitInfo.  IIUC scanning those jars is already 
> implemented.
> 
> 3. I can't get running ddl on a connection from an 
> XADataSource in a simulated "RequiresNew" transaction to work 
> reliably with derby.  The ddl appears to work fine but 
> attempts to read data from the created sequence table hang 
> until the tx times out and derby does not report any 
> deadlocks.  Based on Craig's comments I've added a non-jta- 
> datasource and this seems to be working much better.  Has 
> anyone seen problems like this?  (seems unlikely in this 
> context since i had to modify a bunch of stuff to get to this 
> problem :-)
> 
> many thanks
> david jencks
> 
> On Apr 25, 2007, at 3:56 PM, Patrick Linskey wrote:
> 
> > Inside an appserver, there are parts of the PersistenceUnitInfo 
> > interface that are designed for the appserver to 
> communicate jars to 
> > scan to the persistence provider.
> >
> > -Patrick
> >
> > --
> > Patrick Linskey
> > BEA Systems, Inc.
> > 
> ______________________________________________________________________
> > _
> > Notice:  This email message, together with any attachments, may 
> > contain
> > information  of  BEA Systems,  Inc.,  its subsidiaries  and   
> > affiliated
> > entities,  that may be confidential,  proprietary,  copyrighted   
> > and/or
> > legally privileged, and is intended solely for the use of the 
> > individual or entity named in this message. If you are not the 
> > intended recipient, and have received this message in error, please 
> > immediately return this by email and then delete it.
> >
> >> -----Original Message-----
> >> From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
> >> Sent: Wednesday, April 25, 2007 3:55 PM
> >> To: open-jpa-dev@incubator.apache.org
> >> Subject: Re: More questions on runtime schema generation
> >>
> >> The general solution to this problem lies in a crisper 
> definition of 
> >> classloader domains in the app server. IIUC, each app 
> server has its 
> >> own policies in terms of where various components get loaded and 
> >> when.
> >>
> >> I think we need to engage the server spec team on this, 
> otherwise we 
> >> will end up chasing multiple incompatible class loader strategies, 
> >> all of which turn out to be spec compliant.
> >>
> >> And for a first cut at "reasonable" we might ask the 
> Spring folks how 
> >> they handle this.
> >>
> >> Craig
> >>
> >> On Apr 25, 2007, at 12:26 PM, Patrick Linskey wrote:
> >>
> >>>> However IIUC this dissects the system property 
> java.class.path and 
> >>>> only parses stuff on that.  This might be reasonable for 
> a command 
> >>>> line tool (although I have some
> >>>> doubts) but it seems to me that for any other situation a
> >> scan of the
> >>>> provided classloader would be more appropriate.
> >>>> Is this reasonable?
> >>>
> >>> It is. Of course, there is no standard way to scan
> >> classloaders. The
> >>> best I know of is to do:
> >>>
> >>>     cls.getProtectionDomain().getCodeSource().getLocation()
> >>>
> >>> and then scan from that URL.
> >>>
> >>> Of course, this assumes that a) you have a class (not a
> >> ClassLoader),
> >>> b) you have security privileges to get the protection
> >> domain, and b)
> >>> the location is parsable and accessible.
> >>>
> >>> Is there some other way that you know of to scan a ClassLoader?
> >>>
> >>>> Also, I would like to suggest a flag in the
> >>>> openjpa.jdbc.SynchronizeMappings=buildSchema(...) stuff 
> to turn on 
> >>>> this eager scanning I'm trying to implement.  Does this seem 
> >>>> reasonable?
> >>>
> >>> It does.
> >>>
> >>> --
> >>> Patrick Linskey
> >>> BEA Systems, Inc.
> >>>
> >> 
> _____________________________________________________________________
> >> _
> >>> _
> >>> Notice:  This email message, together with any attachments, may 
> >>> contain information  of  BEA Systems,  Inc.,  its 
> subsidiaries  and 
> >>> affiliated entities,  that may be confidential,  proprietary,  
> >>> copyrighted and/or legally privileged, and is intended solely for 
> >>> the use of the individual or entity named in this message. If you 
> >>> are not the intended recipient, and have received this message in 
> >>> error, please immediately return this by email and then delete it.
> >>>
> >>>> -----Original Message-----
> >>>> From: David Jencks [mailto:[EMAIL PROTECTED]
> >>>> Sent: Wednesday, April 25, 2007 12:18 PM
> >>>> To: open-jpa-dev@incubator.apache.org
> >>>> Subject: More questions on runtime schema generation
> >>>>
> >>>> I'm working on modifications so that ddl can operate in 
> a separate 
> >>>> transaction on a connection from the jta ds and I would
> >> like to have
> >>>> a complete scan and enhancement as soon as possible when
> >> the EMF is
> >>>> first accessed.  I have this working when the classes are listed 
> >>>> explicitly in the persistence.xml but not when they aren't.
> >>>>
> >>>> It looks like the relevant code is AbstractCFMetaDataFactory 
> >>>> getPersistentTypeNames
> >>>>
> >>>>              if (names.isEmpty() && devpath)
> >>>>                  scan(new ClasspathMetaDataIterator(null, 
> >>>> newMetaDataFilter()),
> >>>>                      newClassArgParser(), names, false, null);
> >>>>
> >>>>
> >>>> However IIUC this dissects the system property 
> java.class.path and 
> >>>> only parses stuff on that.  This might be reasonable for 
> a command 
> >>>> line tool (although I have some
> >>>> doubts) but it seems to me that for any other situation a
> >> scan of the
> >>>> provided classloader would be more appropriate.
> >>>> Is this reasonable?
> >>>>
> >>>> Also, I would like to suggest a flag in the
> >>>> openjpa.jdbc.SynchronizeMappings=buildSchema(...) stuff 
> to turn on 
> >>>> this eager scanning I'm trying to implement.  Does this seem 
> >>>> reasonable?
> >>>>
> >>>> thanks
> >>>> david jencks
> >>>>
> >>>>
> >>>>
> >>>
> >>> Notice:  This email message, together with any attachments, may 
> >>> contain information  of  BEA Systems,  Inc.,  its 
> subsidiaries and  
> >>> affiliated entities,  that may be confidential,
> >> proprietary,
> >>> copyrighted  and/or legally privileged, and is intended
> >> solely for the
> >>> use of the individual or entity named in this message. If
> >> you are not
> >>> the intended recipient, and have received this message in error, 
> >>> please immediately return this by email and then delete it.
> >>
> >> Craig Russell
> >> Architect, Sun Java Enterprise System 
> http://java.sun.com/products/ 
> >> jdo
> >> 408 276-5638 mailto:[EMAIL PROTECTED] P.S. A good JDO? O, Gasp!
> >>
> >>
> >
> > Notice:  This email message, together with any attachments, may  
> > contain information  of  BEA Systems,  Inc.,  its subsidiaries   
> > and  affiliated entities,  that may be confidential,  
> proprietary,   
> > copyrighted  and/or legally privileged, and is intended 
> solely for the 
> > use of the individual or entity named in this message. If 
> you are not 
> > the intended recipient, and have received this message in error, 
> > please immediately return this by email and then delete it.
> 
> 

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