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Apache CJAN was an attempt at a simple web service for serving Java Jar files. It was started some time prior to May 2001. It was abandoned in favour of the more promising Apache JJAR project.
Apache JJAR is an experimental distributed repository and toolset to navigate and fetch from the repository. While it met its initial goals and found a couple of niche uses, it never went mainstream due to lack of interest from fellow developers. Although the project is no longer featured on Apache.org's main pages and is essentially abandoned, this experimental project is still hosted on their servers.
Started in November 2001 by Brian Tol, CJAN.org set out to become for the Java community what CPAN represented to the Perl community - a comprehensive archive of reusable components for their respective programming languages.
Two key differences between CPAN and CJAN were that Java uses modules known as Jar files and that CJAN was to use a distributed network topology (the later would ensure that CJAN would scale well with increased numbers of users and keep server hosting costs to an absolute minimum). The decision was taken to code CJAN from scratch in Java.
At the beginning of 2002, Michael Davey started working with Brian on the specifications and a prototype. CJAN.org was managed as an Open Source project, a hobby they worked on in their spare time.
Progress was slow, in part because some of the basic building blocks needed to implement CJAN simply didn't exist in open-source form in Java at that time so the developers were spending time creating the components and then trying to persuade the appropriate developer community to adopt the component and take over its management. The distributed architecture was a problem, too. CJAN was attempting to use the JXTA framework when it was in its infancy and only offered very fine-grained, low-level control of the framework.
Sun Microsystems became interested in CJAN at the beginning of 2003. After some initial discussions with Brian and Michael and then the Apache community they sought the opinion of the wider Java community and teamed up with Collab.Net and O'Reilly publishing. On 11 June 2003 the Java.net community and website was launched.
Ostensibly, CJAN.org failed because it was too ambitious - trying to build an open-source project on leading-edge technology. The final straw for the open-source project was the launch of the high-profile Java.Net website. Although to this day Java.Net does not offer a catalogue of reusable components, it has a huge community and the website features are good enough for most Java developers most of the time that developers rarely cite the need for such.
- Apache.org JJAR is a functional webservice and toolset (at time of writing, JJAR is an abandoned experimental project)
- Java.net CJAN wiki page
- SorceForge.net CJAN project documentation has a number of documents and code, but activity has ceased.
- Java.Net the closest thing the Java community has to a CJAN repository.