Pervasive Java - IEEE Pervasive Computing

1536-1268/02/$17.00 © 2002 IEEE T oday, mobile devices and gadgets come with more than just a cool and cutting-edge design; they come equipped with small brains and a common language, making them smarter and more powerful than ever before. Perhaps they’re a little too smart—after all, they can adapt and morph into each other and become many-in-one super devices. Mobile phones with PDA capabilities and PDAs packaged as mobile phones have started to invade the marketplace. Furthermore, it won’t be long before we can shoot a presentation right off our mobile phones or use a mobile phone as a wireless mouse to more easily surf the Web on a laptop. Appliances are also gaining amazing intelligence, thanks to embedded computers and tiny communication interfaces. Pointof-sale equipment, gas pumps, automobile dashboards, and digital cameras are examples of today’s smart appliances. Refrigerators with Web pads, microwaves that download recipes, and stereo systems that mute when the phone rings are among the many smart appliances on the horizon. The impressive leap in this technology led to a rapid proliferation of many kinds of portable and embedded devices. This proliferation signaled the beginning of a new and exciting era of computing. It also quickly underpinned the new requirements we must meet to mobilize this technology. The most critical requirement was the need for a common yet flexible computing and communication environment that could be fitted for— and shared by—devices of different makes and capabilities. Realizing this need, and recognizing that one size does not fit all, Sun Microsystems introduced the Java 2 Platform, Micro Edition, a set of specifications that pertain to Java on small devices, ranging from pagers and mobile phones to set-top boxes and car navigation systems. Since its introduction, J2ME has evolved according to the Java Community Process, a formalized process and an open organization of international Java developers and licensees whose charter is to develop and revise Java technology specifications, reference implementations, and technology compatibility kits. The J2ME specifications are divided into configurations that are specific to different device categories. Each configuration is specialized into a set of profiles, which are specifications of particPervasive Java