Project Jigsaw goals and requirements

[David Bosschaert]

Thanks for sharing the requirements, Mark.

Like David Lloyd, I have also provided some additional thoughts here:
http://osgithoughts.blogspot.com/2011/05/java-se-8-modularity-requirements.html

Best regards,

David Bosschaert

On 26 May 2011 05:01, David M. Lloyd <david.lloyd at redhat.com> wrote:
> I've posted the first wad of my comments on my blog here:
>
> http://in.relation.to/Bloggers/ModulesInJDK8AndProjectJigsawRequirementsReviewPart1
>
> Feel free to reply there or here, if you want.  I'll follow up with more as
> I have time.
>
> On 05/25/2011 10:55 AM, mark.reinhold at oracle.com wrote:
>>
>> The original goal of this Project was to design and implement a simple,
>> low-level module system focused narrowly upon the task of modularizing
>> the JDK, and to apply that system to the JDK itself [1].
>>
>> We expected the module system to be useful to developers for their own
>> code, and to support it for that purpose, but we did not intend at the
>> outset to propose it for inclusion in the official Java SE Platform
>> specification.  It would have been available in the JDK, that is, but
>> other Java SE implementations would not have been required to include it.
>>
>> We've made a fair amount of progress toward that original goal, having
>> produced the initial working prototype demonstrated at JavaOne in 2009.
>> Work since then has been somewhat sporadic, unfortunately, due to various
>> post-acquisition integration activities and then the intense focus needed
>> to finish and ship JDK 7 according to "Plan B" [2], which deferred Jigsaw
>> to JDK 8.
>>
>> Now that work on JDK 7 is winding down, we're starting to move Jigsaw
>> forward again.  As we do so, it's time to re-evaluate our goal.
>>
>> The need for a truly standard module system for the Java Platform has
>> long been recognized.  If anything that demand has grown in the years
>> since Project Jigsaw was launched.  This was clearly evident at the JCP
>> Executive Committee meeting last October in Bonn, where the long-term
>> convergence of the Java ME and Java SE platforms -- and a module system
>> that could support that goal -- was a major topic of discussion [3].
>>
>> One outcome of those discussions was an informal "modularity summit"
>> organized by IBM and hosted by Oracle this past January in Ottawa.  That
>> meeting included key members of the OSGi, Eclipse, Java SE, and Java EE
>> communities.  Its primary goal was to reach a clear understanding of the
>> requirements of a standard Java module system, and to do so without
>> reference to any particular existing module system.
>>
>> To that end I drafted an abstract module-system requirements document,
>> presented it at the meeting, and then revised it in response to comments
>> and suggestions made at that time and in subsequent discussions.  This
>> was by no means an easy process, but I think it's fair to say that the
>> end result represents the consensus view of all those involved even
>> though a handful of requirements remain open.
>>
>> I've posted the latest draft of the requirements document for wider
>> review [4].  Comments are most welcome.
>>
>> This is still a draft -- I expect it to evolve in response to further
>> comments, and also to expand to include a few more requirements from the
>> Java ME and Java EE communities.  This document will ultimately be one of
>> the starting points for the eventual "Java Platform Module System" JSR
>> that's mentioned in the Java SE 8 Umbrella JSR [5].
>>
>> The requirements document will, in parallel, guide a renewed effort on
>> Project Jigsaw.  We've already prototyped some of the new requirements
>> (e.g., modular JAR files [6]), and work is well underway on some of the
>> others.  The overall Jigsaw design will, once it takes shape, be another
>> of the starting points for the Module System JSR.
>>
>> - Mark
>>
>>
>> [1] http://mreinhold.org/blog/jigsaw
>> [2] http://mreinhold.org/blog/plan-b-details
>> [3]
>> http://jcp.org/aboutJava/communityprocess/summaries/2010/October2010-public-minutes.html
>> [4]
>> http://openjdk.java.net/projects/jigsaw/doc/draft-java-module-system-requirements-12
>> [5] http://www.jcp.org/en/jsr/detail?id=337
>> [6]
>> http://openjdk.java.net/projects/jigsaw/doc/draft-java-module-system-requirements-12#modular-jar-files
>
>
> --
> - DML
>