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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."

David

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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