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From "Patrick Linskey" <plins...@bea.com>
Subject RE: More questions on runtime schema generation
Date Wed, 25 Apr 2007 19:26:08 GMT
> 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.
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> -----Original Message-----
> From: David Jencks [mailto:david_jencks@yahoo.com] 
> 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
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or entity named in this message. If you are not the intended recipient, and have received
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