Note: is in rebuild. Please accept my apologies for broken links, missing stuff, etcetera - more

Jini is not just a technology, but also a community. At first, this might seem odd, but if you think about what is necessary for services to cooperate, it is logical that you want the people that define these services to get together.

Let's go back to my example about the PDF generation service. There was a single line of code in the "mobile code" article:

PdfFile pdf = formattingService.format(xmlFile, styleSheet);

As far as we're concerned, this is the whole interface between the service supplier and the service consumer. Who defines this interface?

There might be many implementations of the service. One implementation could to execute code directly on local computer, the other might just send a work request to a central computer. These various implementations need not be implemented by a single company - they might even be produced by fierce competitors. In fact, that's what you would hope for, because only through competition you get better services. tries to be the place where individuals and organizations cooperate in order to define standard service interfaces for their vertical or horizontal markets, in such a way that they will create an optimal interface definition and still be able to compete with implementations.

The community is defined as everyone who accepted the source code license. This license, the Sun Community Source License, is not an open source license. It attempts to create a level playing field both for individuals want to donate their work to the community and for others who need to protect their intellectual property, but still want to work with the community. There has been a lot of debate over whether not open sourcing Jini was a very wise choice, only time will tell us.

In the meantime, a lot of projects are active on the community's web site ( If you are starting to work with software, it is certainly worth it to pay a visit to the project list on the developer site at (you need to be a community member to access this part of the website).

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