F22 System Wide Change: Legacy implementations of the Java platform in Fedora

[Mikolaj Izdebski]

On 02/24/2015 03:32 PM, Deepak Bhole wrote:
> * Dominik 'Rathann' Mierzejewski <dominik at greysector.net> [2015-02-24 09:29]:
>> On Tuesday, 24 February 2015 at 15:09, Deepak Bhole wrote:
>>> * Dominik 'Rathann' Mierzejewski <dominik at greysector.net> [2015-02-24 09:04]:
>>>> On Tuesday, 24 February 2015 at 14:28, Jiri Vanek wrote:
>>>> [...]
>>>>> There were several attempts in past like "can you please support jdk
>>>>> 7,6...in newer fedoras" and we always told no. When come speech about "do it
>>>>> on your own" suddenly many questions marks raised up.
>>>>>
>>>>> The last open bug is: https://bugzilla.redhat.com/show_bug.cgi?id=1190137
>>>>> the guy is willing to maintain it.
>>>>
>>>> Fine, so let him do it and drop the Obsoletes: tag in java-1.8.0-openjdk
>>>> and its successors. You shouldn't arbitrarily block people from
>>>> re-introducing an older branch of any package back into Fedora in the
>>>> first place.
>>>>
>>>
>>> We have no intention of blocking it. The reason for proposing these
>>> restrictions is that the Fedora Java stack will not work with older
>>> JDKs, therefore we need to make sure that it goes not get installed on
>>> the system unless explicitly requested by someone who knows what they
>>> are doing.
>>
>> Well, you do that by adding/updating (Build)Requires: in the packages
>> which won't work otherwise, not by adding Obsoletes:.
>>
> 
> That would generally work for most packages, but there is a new JDK
> released every 2 years. This means that we would have to change the BR
> and Requires for the entire Java stack (100s and 100s of packages) every
> 2 years, which is non-trivial.

First, we have versioned auto-requires generated during package build.
Explicit requires on java aren't usually needed. If package requires
"java > 1:1.7" then it is correct - the package can be assumed to work
with older JDK.

Secondly, it is fairly easy to add requires on "java-devel >= 1:1.8" to
packages related to build systems like ant, maven or gradle. This would
cover most cases of building Java packages using latest JDK.

-- 
Mikolaj Izdebski
Software Engineer, Red Hat
IRC: mizdebsk