RFR: 8152423: Generated temp files (+JXF...temp) for custom fonts not deleted on exit.

[Phil Race]

See updated webrev and comments at 
https://bugs.openjdk.java.net/browse/JDK-8152423

-phil.

On 05/05/2016 12:16 PM, Jim Graham wrote:
> In that case, in order to avoid race conditions (GC could be 
> accidentally triggered by this or subsequent shutdown hooks in the 
> system), it should be released by calling disposer.dispose() instead 
> of directly calling Release (still setting fontFace to null just in 
> case).  That will ensure only one release per fontFace.
>
> Also, in the constructor it looks like we'll construct a disposer for 
> a null fontFace.  I don't think it hurts anything, and probably 
> shouldn't happen in practice, but still seems odd...
>
>         ...jim
>
> On 05/05/2016 11:40 AM, Phil Race wrote:
>>
>> On 05/05/2016 11:26 AM, Jim Graham wrote:
>>> Is this true of any other objects managed by DWDisposer?
>>
>> DWDisposer is only the class used to implement "dispose()" of
>> a  single DWFontFile that occurs during running/gc.
>>
>> It doesn't really "manage" anything and I don't see it used
>> to dispose any other resource.
>>
>>> Would it be better to simply run through the DWDisposer queue on
>>> shutdown and force it to dispose (i.e. release) everything it has?
>>
>> There isn't a "DWDisposer" queue - it is the shared disposer queue for
>> all resources across Prism - so far as I can tell anyway.
>>
>> This clean up on exit of font files is initiated from a shutdown
>> hook specific to the temporary font files (shared, not DW specific).
>> To be able to delete the files we need to be sure that Release() was
>> called before File.delete().
>> So we either would need the font file shutdown hook to take ownership
>> of first releasing other Prism resources as well or find a way to kick
>> off a different
>> hook specific to DWDisposer and ensure it runs before the deletion hook.
>> I am not sure there is any way to guarantee that order.
>>
>> Also if we do an 8ux backport I'd want to do it this simpler way there
>> even if something different were done for 9.
>>
>> -phil.
>>
>>>
>>>             ...jim
>>>
>>> On 05/05/2016 11:12 AM, Phil Race wrote:
>>>> Please review :-
>>>> Bug : https://bugs.openjdk.java.net/browse/JDK-8152423
>>>> Fix : http://cr.openjdk.java.net/~prr/8152423/
>>>> <http://cr.openjdk.java.net/%7Eprr/8152423/>
>>>>
>>>> "Release" was not being called on the DirectWrite font object
>>>> so it held a reference to the file, which on Windows prevents
>>>> the file from being deleted.
>>>>
>>>> -phil
>>