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Date: Mon, 14 Jun 2010 13:47:22 +0200
From: Kristian Waagan <Kristian.Waagan@Sun.COM>
Subject: Heads up: upcoming minor changes to the Derby build JDK
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To: Derby Development <derby-dev@db.apache.org>
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Hello,

I believe that it is soon time to reorganize the code living in 
PropertySetter. As mentioned by Rick, it has evolved significantly since 
its inception. This is, however, a separate issue.

For now, I'd like to implement a few improvements:
  a) don't add Java 6 libraries when compiling with a Java 5 compiler 
(tracked somewhat incorrectly under DERBY-3989, see comments at the end)
  b) fix broken logic for newer OS X installations (DERBY-4694)
  c) disable (and remove) original detection algorithm

a) should have minimal impact, since the disallowed (or skipped) 
configuration will result in a failed build (wrong class version). If 
the configuration is specified explicitly, the build will be aborted 
with a sensible error message. If the configuration is detected by 
PropertySetter, the Java 6 libraries will be ignored.

b) affects only Mac users, the problem was reported by a Derby user.

c) is a bit more unclear, but I believe it should be reasonably safe. 
The problem with the old algorithm, is that it doesn't verify the JDK 
installation as well as the new algorithm (which only runs a few more 
checks). To my knowledge, this can happen on default installations of 
some Linux distros.


I'll commit a) shortly, follow up with b) within a few weeks, and 
finally commit c) (a new Jira will be created).
Please let the list know if any of the changes break your build.


Regards,
-- 
Kristian