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From "David W. Van Couvering" <David.Vancouver...@Sun.COM>
Subject Re: PLEASE READ AND REVIEW: Proposed text for code sharing contribution
Date Wed, 09 Nov 2005 22:41:33 GMT
Yes, that's correct, that's the intent of the forward-compatibility 
guidelines and mechanisms.

I could add this text:

"Older versions of Derby jars will get their expected behavior in a 
mixed version environment regardless of jar ordering.  Newer versions of 
Derby jars will get their expected behavior as long as the newer jar 
files are loaded first."


Kathey Marsden wrote:
> David W. Van Couvering wrote:
>>This contribution provides mechanisms and guidelines, such as
>>guidelines and tools for supporting forward and backward
>>compatibility, to help ensure that Derby jars with different versions
>>can be loaded in a Java VM without having to use specialized
>>classloaders.  If an incompatibility exists between versions, it will
>>be clearly documented.  Any undocumented incompatibilities will be
>>treated as a bug.
>>However, not all issues can be resolved.  For example it is possible
>>for "shadowing" to take place if there are different versions of
>>network client and embedded client in the same VM, and each provides a
>>different implementation of the same common method.
> I think that it would be good to communicate  that in such cases 
> regardless of the order the jars are loaded,  functionality will not be
> affected at the lower revision level for either the embedded or client
> jar.  The  higher revision behaviour  can be used if the higher revision
> jar is loaded first.
>  Is that true?  And if so can we include it  in the vote?
> For instance if I have a 10.2 derbyclient.jar  and a 10.3 derby.jar in
> the same JVM,  everything should work ok at the 10.2 level regardless
> of  class loading order, but If I put derby.jar first,  the embedded
> application  should be be able to function at the 10.3 level and the
> client at the 10.2 level.
> Thanks

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