Chapter 22. A Sneak Peak at Jini Technology

Forward-looking companies are always trying to re-invent themselves before someone else does, especially in the software industry. After developing the C programming language, AT&T developed C++. After Windows 95 introduced millions of PC users to new desktop metaphors like the "My Computer" and "Network Neighborhood" icons, Windows 98 changed the default interface paradigm from the familiar Windows desktop to a browser interface based on Internet Explorer. Many of the software trends in recent years have been propelled forward at breakneck speeds by the rapid adoption of the Internet and its underlying technologies such as TCP/IP, HTML, and the Java platform. With over three years having passed since the introduction of Java technology by Sun Microsystems, one can only wonder what the Sun research labs have been working on for a follow-on. In the recent summer of 1998, Sun's Vice President of Research, Bill Joy, broke three years of silence to talk about Sun's R&D project to develop Jini technology.

Jini is not a new software language or hardware technology. In fact, Jini is based on Sun's Java platform. What Jini does is dramatically expand the power of Java technology to allow spontaneous networking for a wide variety of hardware and software. Jini allows people to use networked devices and services as simply as they would use a phone today. Think about it. You can unplug your home phone today and plug it in at your friend's home without any doubt that you would get a dial tone and be able to make a call. Can you say the same about plugging in your laptop and being able to use your friend's printer? The very terms "plug and play" have been associated with a PC-centric paradigm, plugging new devices into your PC. Jini technology expands on "plug and play" to define a new metaphor of "plug and participate" from a network viewpoint based on network dial tone.

Because Jini takes advantage of Java technology, it can be easily recognized by the more than one million Java programmers in the world. Jini consists of a small amount of Java code, packaged as Java class libraries, and some conventions used to create a "federation" of Java virtual machines. Today, Jini technology could be applied to the 100 million+ Java virtual machines running on every type of computer as we know it. Now think again about Jini technology enabling several billion ^[1] Java virtual machines inside printers, disk drives , cell phones, PDAs, virtually any microprocessor- powered device with some sort of network port. Jini technology allows all devices in a network to be dynamically connected to share information and perform tasks . Just as HTML is about to become a universal document format, ^[2] Jini technology promises to provide a universal resource sharing over network dial tone. This chapter provides a sneak peak at the infrastructure components and distributed programming model of the Jini platform.

^[1] Sun estimate that by the year 2000, the semiconductor industry will produce 10 billion microprocessors per year, with roughly 25% or 2.5 billion of these capable of running a Java virtual machine.

^[2] Microsoft has announed that the office 2000 product suite will use HTML as the defult file format.