[9] RFR (XS): 8169000: Define reference reachability more precisely in java.lang.ref package

[Hans Boehm]

The rather-hard-to-decode section 12.6.2 essentially tries to pin down
exactly when a reference is guaranteed to remain reachable. It may be worth
directly pointing to it. (And perhaps wishing the reader luck :-) )

On Wed, Nov 16, 2016 at 12:21 AM, Zoltán Majó <zoltan.majo at oracle.com>
wrote:

> Hi David,
>
>
> On 11/16/2016 03:21 AM, David Holmes wrote:
>
>> Hi Zoltan,
>>
>> First, I'm okay with latest webrev.
>>
>
> thank you.
>
>
>> Second, I don't want to confuse things but need to correct one thing ...
>>
>
> I think you rather clarified things.
>
>
>> On 15/11/2016 10:41 PM, Zoltán Majó wrote:
>>
>>> [...]
>>>
>>> For example, statement (2) can be possibly (mis-)read as the JVM making
>>> references unreachable *earlier* than what a programmer may think --
>>> based on the source code.(That is clearly not the case: References are
>>> available at least until the latest program point where they are used,
>>> otherwise the program would encounter an error.)
>>>
>>
>> Actually it can make references unreachable earlier than may be expected.
>> The wording Mandy suggested comes from the JLS itself - see 12.6.1.
>>
>
> That is right -- thank you for pointing to the relevant section of the JLS.
>
> (Though I agree it isn't the right disclaimer for the current situation -
>> where the interpreter keeps the reference reachable longer than naively
>> expected).
>>
>
> Please see my reply to Mandy's email.
>
>
> Thank you!
>
> Best regards,
>
>
> Zoltan
>
>
>
>> David
>> -----
>>
>> It's indeed a JVM "optimization" keep references alive *longer* than it
>>> seems to be from the source code. But (1) already encapsulates that
>>> without referring to JVM optimizations explicitly.
>>>
>>> [...]
>>>>
>>>>
>>>> Making it clear “strongly reachable” is a good suggestion.  I don’t
>>>> see word-smithing is needed in the original sentence; hence my above
>>>> suggested change only adds the word “strongly” in this sentence.
>>>>
>>>
>>> I agree.
>>>
>>> Here is the updated webrev:
>>>
>>> http://cr.openjdk.java.net/~zmajo/8169000/webrev.02/
>>>
>>> Thank you!
>>>
>>> Best regards,
>>>
>>>
>>> Zoltan
>>>
>>>
>>>> Mandy
>>>>
>>>
>>>
>