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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 Thu, 10 Nov 2005 01:04:07 GMT
Yes that's right.  In general things should still work, even if they 
don't work in the "new way."  We should never have an *accidental* 
situation where something just doesn't work (e.g. MethodNotFound or 
whatever the exception is).  It may be that we are forced to introduce 
functionality that is not forward-compatible, but that is to be avoided.

So, how about

"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 new behavior if the newer jar files are loaded 
first, and older behavior if the older jar files are loaded first.

There should never be an where Derby can not find the common code it 
needs due to mixed versions.  Such incompatibilities should be avoided 
as much as possible, and where they are unavoidable, should be 
documented and introduced only as part of a major release.  Any 
unexpected and undocumented incompatibilities should be treated as a bug."


Kathey Marsden wrote:
> David W. Van Couvering wrote:
> 
> 
>>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."
> 
> 
> But it is also important that the newer jars still work at the lower
> revision level even if they are not loaded first.  Will that be the case ?
> For instance if  I have a 10.2 client and a 10.3 server with the client
> loaded first,  all of the 10.2 functionality even if it uses shared code
> should still work for the server.   We always need to at least negotiate
> down to the lower level and I don't think your sentence says that.
> 
> 
> 

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