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From "Mattmann, Chris A (388J)" <>
Subject Re: [Proposal] Accept Jena into the Incubator
Date Tue, 09 Nov 2010 00:32:23 GMT
Big +1 from me.


On 11/8/10 6:36 PM, "Ross Gardler" <> wrote:

I am pleased to offer, for your consideration, the following proposal to
accept Jena, a semantic web framework into the incubator. The text of
the proposal is copied here for your convenience and can be found at

We currently have two mentors so we're looking for at least one more.

Note that there is already an overlapping discussion about interaction
between this and other semantic web projects in the incubator. As
champion of this proposal I have recommended that the Jena team
participate in this discussion. I'm not able to speak for the Jena
committers, but I am keen to see *appropriate* sharing of code between

However, I don't believe that this should be forced upon the three
projects as part of their incubation. Such collaboration should emerge
through community engagement, with mentor guidance, rather than through
incubator conditions of entry or graduation.

Comments and volunteers welcome.

Now for the proposal:

= Jena, a Semantic Web Framework =
== Abstract ==
Jena is a semantic web framework for Java, based on W3C standards.

== Proposal ==
Jena provides a semantic web framework in Java that implements the key
W3C recommendations for the core semantic web technologies of RDF and
SPARQL.  Jena is a number of components and modules built on this core
system.  It currently includes:

  * an API for working with RDF
  * Parsers and writers for the RDF formats (RDF/XML, Turtle, N-triples,
NQuads, TriG)
  * an implementation of SPARQL, the W3C standard RDF query language
  * multiple storage systems for RDF data including in-memory,
file-backed, in SQL databases and in custom scalable storage systems
  * an API for manipulation of OWL
  * a rule-based inference engine
  * an implementation of GRDDL for extraction of RDF from XML formats
  * a standards compliant IRI library.

The project includes facilities based around this core to encourage the
  creation of components and contributions both as part of Jena and also
  as companion open source activities.

This proposal includes the main components of Jena: the main Jena
download, ARQ, GRDDL, SDB, TDB, the IRI  library and Joseki.  Other
components may be contributed later - we're  just starting with the main
part of Jena for now.

== Background ==
The W3C recommendations provide detailed specifications and it is
important to follow these standards so that independently built
applications can exchange data over the web.  Jena provides high quality
  Java implementations of RDF input/output and storage so that
application  writers can concentrate on the application, not the
low-level details.

W3C Semantic Web:

Jena has been on !SourceForge since 2001.

== Rationale ==
The open source project was originally created as part of a research
activity in HPLabs.  In building new systems, the researchers identified
  the value of a common platform that dealt with the low level details
of  the standards.  This lead to engagement with the standards process
and  the creation of a framework that provided a library to deal with
the  details of semantic web standards.  This work was released as Jena.
The  developers have contributed implementation experience back to the
working groups.

None of the contributors now work for HP.  Providing a uniform
contributor and licensing framework assists commercial use of Jena.

== Current Status ==
Jena is already an established project with a large user base in
industry and academia.  It currently uses a BSD-style three-clause
license with a number of contributing copyright holders. Support is
primarily provided via the mailing list. The
majority of the team was employed in HPLabs, and HP holds the majority
of the copyright over the code - there are contributions from non-HP
companies.  HP decided to close the research group as of October 2009
and the people from HPLabs connected with the project have moved on to
several different semantic web companies.

This change does not immediately affect Jena because the people who were
  in HP still remain active contributors to Jena.  The project continues
to be supported and actively enhanced.  There is now the  opportunity to
become an open source project without a single large  organisation involved.

=== Meritocracy ===
The Jena team has always been self-determining; there has not been a
project manager in charge of the effort.  Instead, it has grown through
  individuals contributing to the codebase as part of their research
activities.  The team has organised itself to create the framework for
builds, releases and public support, and people who had worked on Jena
in HP, and moved to other companies and institutions, have continued to

=== Core developers ===

Jena originated within a research activity in HPLabs, starting around 2000.
Contributors to jena have been active in W3C working groups including
chairing the "RDF Core" working group and acting as document editors on
several other working groups.  W3C processes are public; jena contributors
have been involved in public debate and decision making.  People have since
moved on from HP to several semantic web forced companies and to university

=== Alignment ===
Jena is already in use in many commercial systems as well as widely used
  in academic research and teaching.  We want to continue making this
easy  and at the same time encourage contribution in a well-known

Jena is already pretty much run in a collaborative open development
style with communication on mailing lists.

== Known Risks ==
=== Orphaned products & Reliance on Salaried Developers ===
Jena is in use by companies we work for so the companies have an
interest in its continued vitality.

The Jena team members are not employed to work on Jena specifically;
while there is some development as part of their day-jobs, the team
members do also contribute personal time as well.

=== Inexperience with Open Source ===
While Jena has been open-source since 2001, the majority of individuals
  involved do not have wide experience of contributing to other open
source projects, so the team members need to develop more skills in
participating in open-source communities.

=== Relationships with Other Apache Products ===
Jena uses Xerces, Lucene, Apache Commons HttpClient and Apache Commons

Jena is used by Clerezza (in incubation).

=== A Excessive Fascination with the Apache Brand ===
Jena has an established community of users and is used in both academic
  and commercial settings.  The Apache environment offers Jena the
opportunity to expand the ways that more people can be involved and
contribute, and hence to ensure the project is not dependent on the
current members.  We hope that association with Apache will also
encourage other open source projects that use Jena to help develop a
healthy and vibrant semantic web open source ecosystem.

Apache offers us a clear licensing framework and support infrastructure
which would reassure the many users of Jena who exploit it in commercial
environments as well as those in other open source projects.

== Documentation ==
Overview documentation, tutorials, topic-based how-tos and detailed
!JavaDoc can be found at

== Initial Source ==
The majority of the current codebase resides in the Jena project CVS/SVN
  on !SourceForge.  Joseki is also on !SourceForge; we later decided to
put all  projects under one SF project so this is a historical anomaly.
The modules in the initial source are:

  * [[|Jena CVS area on
   * jena2 (the core system, include RDF, rules and OWL subsystems)
   * iri (the IRI library)
   * Eyeball and !EyeballAcceptance (a checker for RDF)
  * [[|Jena SVN area on
   * ARQ (SPARQL query and update engine)
   * Fuseki (SPARQL server)
   * grddl (GRDDL implementation for Jena)
   * SDB (SQL database layer for Jena)
   * TDB (customer storage layer for Jena)
   * Ymris (experimental rules engine)
   * Experimental/Jena3 (experiment reorganisation of jena)
  * [[|Joseki
CVS area on SourceForge]]
   * Joseki3 module.

== Source and Intellectual Property Submission Plan ==

We are in discussions with HP, the largest copyright holder, about
licensing to Apache and currently HP has indicated that it is willing to
  do so in principle.

== External Dependencies ==
Details of license of components used by Jena are available at:

The Jena GRDDL Reader has some additional dependencies:

We are heavily dependent on Xerces for both parsing and also for XML
datatype support.

== Cryptography ==
No specific cryptography.

== Required Resources ==
Mailing lists

  * jena-private (with moderated subscriptions)
  * jena-dev
  * jena-commits
  * jena-user

Subversion Directory

  * jena

Issue Tracking

  * JIRA

Other Resources

  * Hudson

== Initial Committers ==

The intial committers are the currently active developers for Jena.

  * Chris Dollin
  * Paolo Castagna
  * Damian Steer
  * Jeremy Carroll
  * Ian Dickinson
  * Dave Reynolds
  * Andy Seaborne

== Affiliations ==

  * Epimorphics Ltd: Dave Reynolds, Ian Dickinson, Chris Dollin, Andy
  * Talis Systems Ltd: Paolo Castagna
  * University of Bristol: Damian Steer
  * Top``Quadrant Inc: Jeremy Carroll

== Sponsors ==
=== Champion ===
Ross Gardler (rgardler .at.

=== Nominated Mentors ===
  * Bertrand Delacretaz bdelacretaz .at.
  * Leo Simons  leosimons .at.

=== Sponsoring Entity ===
Incubator PMC

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Chris Mattmann, Ph.D.
Senior Computer Scientist
NASA Jet Propulsion Laboratory Pasadena, CA 91109 USA
Office: 171-266B, Mailstop: 171-246
Adjunct Assistant Professor, Computer Science Department
University of Southern California, Los Angeles, CA 90089 USA

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