Titanomachia Server Components

Servlet Framework

The Servlet Framework is the first set of components to be worked on in the Titanomachia Server Components for Java distribution. The intent of the Servlet Framework is to encapsulate the JSDK (Java Servlet Development Kit) into an event driven framework to reduce the mundane coding required to implement a Servlet in Java.

This is accomplished via a derivative of javax.servlet.http.HttpServlet which controls event processing. A Servlet within this framework can have any number of event handlers for low-level HTTP operations (i.e. GET, POST, PUT, etc.), but only one renderer. Note: the renderer could be a compound renderer implemented using the extensions package ServletListener implementations.

An event handler is where the application control goes. The event processing mechanism in the Servlet Framework is similar to the event processing performed in the AWT or JFC. The basic framework merely provides the event listener interface, however many extension implementations for conditional and algorithmic event processing exist within the package org.titanomachia.servlet.extension.

A renderer is an event handler that draws a servlet, or more specifically generates the output of the servlet. As previously mentioned, for each HTTP operation there can be only one renderer. However, this renderer could be a concrete implementation of an extension handler.

As part of both testing and documentation, the package org.titanomachia.sample was created. The sample servlets attempt to document framework usage by presenting common sample applications. It is usually recommended that first-time users start there for learning how to use the framework.

The servlet framework has also been extended to provide servlets that emit XML and XML/XSL. Servlets that generate XML documents are predominantly used to either serve data to applications and processes that access the server programmatically or web applications that utilize client-side XSL translation. Servlets that generate XML/XSL basically are web applications that generate XML documents, but the XSL translation occurs on the server-side.

The XML/XSL solution has been used on several deployed web applications of varying size, and has proven to be quite successful both in terms of execution speed and development time. There is a learning curve for XML/XSL, but this learning curve is not terribly steep. One of the primary benefits for the XML/XSL approach over conventional servlets or JSPs is that the Model and View are distinctly separate entities and can be deployed indpendently. Furthermore, a web-savvy non-programmer can implement a new user interface without modifying application source code. Finally, a bare-bones user interface can be implemented to jump start development of actual business functionality without the typical holy wars of UI design.