The Jini(TM) Specification (The Jini(TM) Technology Series)

Jini(tm) technology represents a significant step in the evolution of distributed computing, as a simple yet remarkably reliable and flexible infrastructure that enables all types of devices to simply connect into impromptu networks, making access to and delivery of new network services as simple as plugging in a telephone. Built on top of a Java software infrastructure, Jini technology enables all types of digital devices to work together in a community organized together without extensive planning, installation, or human intervention. In a Jini distributed system, Java programs interact spontaneously, enabling services to join or leave the network with ease, and allowing clients to view and access available services with confidence. A Jini system can link office components such as printers, faxes, and desktop computers. Beyond these traditional networks, the technology is also ideal for building the home-based networks that are now emerging: entertainment systems, cars, smart houses, and personal computers.

This book contains the formal specification for the Jini technology. It offers a review of distributed computing fundamentals, an overview of the Jini architecture, and an introduction to the key concepts that are the source of the technology's simplicity and power--remote objects, leasing, distributed events, and a two-phase commit protocol. The formal specification provides the definitive description of every element of the Jini architecture, including detailed information on such topics as:

* Jini Discovery and Join protocols * Jini Entry usage and the AbstractEntry class * Jini Distributed Leasing concepts * Jini Distributed Event programming model * Jini Transaction model and semantics * Jini Lookup service and lookup attribute schema * Jini device architecture

As networks continue to pervade our personal and professional lives, there is an urgent call for the flexible and robust network infrastructure that Jini represents.

What does Sun's Jini technology mean for the future of distributed computing? To find out, take a look at The Jini Specification, a guide written for IS managers and Java developers alike.

The book starts with what Jini is and how it works. (In short, Jini allows Java clients to invoke remote services easily through Java.) The authors present a chat message server and explain the Jini architecture where clients look up and "lease" remote services.

The heart of this book is its coverage of classes in the Jini specification. First there's an overview of Jini illustrated with a printer service. Then it's a close look at how clients "discover" Jini services, either through multicast or unicast protocols. (The authors also present useful built-in utility classes here.)

Next comes material on storing entries for Jini services (used for identifying them across the network) and the classes used to "lease" remote services. An interesting section on remote events contrasts them with local JavaBean events. Then it's on to Jini transactions, including the two-phase commit process used to manage work done remotely.

Later the book turns to the new JavaSpaces classes, which permit sharing data between Java processes in order to facilitate parallelism. An intriguing appendix reprints a white paper in which the Sun team outlines its philosophy of distributed computing. (They argue that local and remote objects need to be handled differently: object location transparency is a myth.)

With a mix of technology briefing and nuts-and-bolts detail, The Jini Specification delivers a valuable perspective on the latest advance in Java distributed computing from Sun. --Richard Dragan