Develop WAP Applications with Java Servlets and JavaServer Pages

Wireless networks are mainly used for voice communication. Wireless operators, however, are interested in delivering data over wireless networks. Having become a new buzzword, WAP (Wireless Application Protocol) is designed specifically for delivering Internet data over wireless networks. This article introduces you to WAP and its related technologies (WML, WMLScript, and so forth), and shows you how to develop wireless applications using Java technology.

Most Internet technologies have been designed for desktop and large computers running on reliable networks (with relatively high bandwidth). Handheld wireless devices, however, have a more constrained computing environment compared to desktop computers. Handheld devices tend to have less memory, less powerful CPUs, different input devices, and smaller displays. Further, wireless networks have less bandwidth and more latency compared to wired computer networks.

WAP, the Wireless Application Protocol, was designed to take advantage of the several data-handling approaches already in use. WAP integrates the Handheld Device Markup Language (HDML) and the Handheld Device Transport Protocol (HDTP) developed by Unwired Planet (now known as Phone.com), as well as Nokia's Smart Messaging Protocol (SMP), and Ericsson's Intelligent Terminal Transfer Protocol (ITTP). WAP services can be hosted on Web servers using technologies such as Java servlets and JavaServer Pages(JSP). In this article, I show you that WAP and Java are complementary, not competing, technologies. WAP is meant for cellular phones, and Java aims at more sophisticated network terminals.

The WAP platform is an open specification that addresses wireless network characteristics by adapting existing network technologies (and introducing new ones where appropriate) to the special requirements of handheld wireless devices. Therefore, WAP intends to standardize the way wireless devices (mobile phones, PDAs, and so forth) access Internet data and services. WAP's reuse of existing Internet protocols will ease the development of WAP services for Java and other Web developers.

To facilitate the delivery of Internet data to wireless devices will certainly lead to the introduction of new technology. For example, wireless devices have small screens compared to desktop computers, and therefore HTML (which is visually rich) is not appropriate for small screens. The small screen and the computing power, which is increasing, represent a limiting factor in running complicated Java applications with intensive graphics. However, efforts are being made for having a compact subset of the Java language suitable for mobile applications. In this article, you learn how to develop WAP applications using Java servlets and Java Server Pages.

But first, I describe the WAP platform and how it incorporates several technologies that are similar to existing ones but that have been designed specifically for wireless devices.