JSP Technology -- Friend or Foe?

 A critical look at JavaServer Pages servlets as a viable presentation technology

An old Java technology hand and new Enhydra partisan, the author urges developers to consider alternatives to JavaServer Pages (JSP) servlets when choosing an approach to coding Web applications. JSP technology, part of Sun's J2EE platform and programming model, serves as a solution to the common dilemma of how to turn drab content into a visually appealing presentation layer. The fact is, Web developers aren't uniformly happy with JSP technology. Since many variations on the Sun technology are now available, you can choose from a number of presentation technologies. This article takes an in-depth look at JSP coding and explores some attractive alternatives.

Presentation technology was designed to transform plain ol' raw Web content into content wrapped in an attractive presentation layer. JavaServer Pages (JSP) technology, Sun's presentation model and part of the J2EE platform, has received significant attention. There are both advantages and disadvantages to using JSP technology, and Web developers should be aware of the good and the bad -- and know that they don't have to be limited to this single technology. In fact, these days a number of presentation technologies are available. This article begins by defining the problems presentation technologies were designed to solve. It then examines the specific strengths and weaknesses of the JSP model. Finally, it introduces some viable alternatives to Sun's presentation technology.

A bit of history

Before diving into an explanation of presentation technology, it's helpful to fill in some details on the situation that led to the birth of the technology. Just 10 short years ago, the term thin client was a novelty. We still lived in a world of desktop applications, powered by wimpy 286 microprocessors with 14-inch monitors that we squinted at. Boy, have times changed! Now my desktop does nothing but power a Web browser, while servers from Sun, IBM, HP, Compaq, and the rest churn out computations, business logic, and content. And that little monitor? Replaced by flat-screen, plasma, whopping 21- and 25-inch beauties. Why? So we can see the intricate and complex HTML displays that serve as a front-end to these powerful applications. No longer does a clunky interface suffice; now we expect flashy graphics, moving images, color-coordinated presentations that would look good in any room in the house, and speedy rendering to boot.

The premise

Today, a decade beyond those fledgling Windows applications, we are still dealing with this huge shift in the presentation paradigm. The woeful Visual Basic and C programmers who remain now find themselves working either on back-end systems or Windows-only applications, or they have added a Web-capable language such as the Java language to their toolbox. An application that doesn't support at least three of four ML-isms -- such as HTML, XML, and WML -- is considered shabby, if not an outright failure. And, of course, that means we all care very deeply about the ability to easily develop a Web presentation layer.

As it turns out, using the new Internet, and all the languages we have at our disposal -- Java, C, Perl, Pascal, and Ada, among others -- hasn't been as easy as we might have hoped. A number of issues creep up when it comes to taking the programming languages everyone used for back-end systems and leveraging them to generate markup language suitable for a client. With the arrival of more options on the browser (DHTML and JavaScript coding, for example), the increase in graphic artist talent in the Web domain, and tools that could create complex interfaces using standard HTML, the demand for fancy user interfaces has grown faster than our ability to develop these front ends to our applications. And this has given rise to presentation technology.

Presentation technology was designed to perform a single task: convert content, namely data without display details, into presentation -- meaning the various user interfaces you see on your phone, PalmPilot, or Web browser. What are the problems that these presentation technologies claimed to solve? Let's take a look.