Proposed implementation of JEP 182 in JDK 11: drop javac support for -source/-target/--release 6

[Stephen Colebourne]

Thanks, it makes a big difference to have an LTS release with modules
and JDK 6 support
thanks
Stephen

On 16 May 2018 at 00:51, Joseph D. Darcy <joe.darcy at oracle.com> wrote:
> Hello,
>
> Based on the feedback on this thread and elsewhere, I've targeted
>
>     JDK-8028563: Remove javac support for 6/1.6 source and target values
>     JDK-8173606: Deprecate constructors of 7-era visitors
>
> to JDK 12.
>
> Thanks,
>
> -Joe
>
>
> On 5/10/2018 10:56 AM, joe darcy wrote:
>>
>> Hello,
>>
>> As background, JEP 182 "Policy for Retiring javac -source and -target
>> Options" (http://openjdk.java.net/jeps/182) puts forth a "one plus three
>> back" policy for the supported range of -source and -target arguments to
>> javac. (As of JDK 9, a matching range of arguments is supported for the
>> --release option.)
>>
>> This policy was formulated under the old release model before the six
>> month release cadence.
>>
>> Under this policy, support for the 5/1.5 argument was removed in JDK 9.
>> JDK 10 added support for a 10 argument and retained all the older values
>> that were supported under JDK 9.
>>
>> JDK 6 first shipped at the end of 2006, which will be nearly 12 years
>> before the planned JDK 11 GA date. JDK 7 first shipped in 2011.
>>
>> Given the age of JDK 6, I think it is reasonable in 2018 for JDK 11 to
>> drop support for -source/-target/--release 1.6/6, leaving support for 7, 8,
>> 9, 10, and 11. This provides support for four rather than three older
>> versions in JDK 11, but better matches the time span of releases discussed
>> in the JEP.
>>
>> Future code reviews of the implementation of this removal and related work
>>
>>     JDK-8028563: Remove javac support for 6/1.6 source and target values
>>     JDK-8173606: Deprecate constructors of 7-era visitors
>>
>> would take place on compiler-dev.
>>
>> Comments?
>>
>> Cheers,
>>
>> -Joe
>>
>