JEP proposed to target JDK 11: 336: Deprecate the Pack200 Tools and API

Peter jini at
Sat Jun 16 10:32:54 UTC 2018

Hi Mark,

Might Oracle consider donating only the specification doc's and jtreg 
tests to Apache?   We don't need the implementation.

I've started working on  Emmanual's Pack200 implemetation from Apache 
Harmony, so far I've got it working and all tests passing with ASM6.2.  
I'd like to get it up to date with the latest jvm bytecode features, the 
tests would certainly help, as it currently only supports java 1.5 and 
some 1.6 features.   This implementation of Pack200 is modular, 
separable and should be relatively easy to maintain, external to the 
JVM.  Perhaps Oracle / OpenJDK could retain the api within the jvm, but 
drop the implementation in a future release, we could use the existing 
provider mechanism.



On 16/06/2018 12:23 AM, mark.reinhold at wrote:
> 2018/6/14 16:56:41 -0700, Emmanuel Bourg<ebourg at>:
>> ...
>> Do I understand correctly that pack200 will be in JDK 11 but might be
>> removed in a later release?
> Yes.
>> If maintaining this technology is a burden for Oracle, could community
>> involvement help reverse this decision?
> Possibly.  As noted in the JEP, however, Pack200 is a complex and
> elaborate technology that’s tightly coupled to the class-file format
> and the JAR-file format, both of which continue to evolve.  This isn’t
> a reasonably-separable component that can be maintained more or less
> at its own pace.  If one or more non-Oracle contributors were to step
> up to maintain Pack200 then they’d need to commit to staying on top of
> it and participating in most every six-month feature release.
> - Mark

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