2.3.2 Tomcat Servlet Engine and Web Server
Web applications today are based on the ability of the server to generate flexible, dynamic
content. Several technologies are available that address dynamic content generation
Microsoft's Active Server Pages technology (ASP), Java Server Pages and Servlets, or PHP are
examples to name but a few.
Tomcat is the Servlet and Java Server Pages reference implementation (quote from the
Tomcat Web site
). To explain this statement further: While the
Servlet and Java Server Pages technologies are owned by Sun, the development of an engine
actually using these technologies has been put under the responsibility of the Jakarta Apache
Project. Jakarta is the home of several Open Source projects that all have Java as the common
platform. Tomcat is one of these projects.
In addition to being a Servlet and JSP Engine, Tomcat can also be used as a Web server. This
is especially useful during development for testing, when performance is not a critical issue. For
deployment, however, it is recommended to use Tomcat in conjunction with a more stable and
faster Web server, such as Apache.
The latest version of Tomcat can be downloaded at the Internet address given above. On line
documentation covers installation on Windows or Linux, as well as other topics such as Apache
Tomcat Web server integration, or application development under Tomcat. Some of these topics
are covered later on in this document.
2.3.3 Enhydra Application Server
188.8.131.52 Introduction to Enhydra
Enhydra provides a development environment for creating Web applications, being the Open
Source alternative to commercial software products that typically cost several thousand or up to
tens of thousands of dollars per CPU (e.g. WebSphere by IBM, iPlanet Application Server by
Sun). Enhydra is available for free download at
, or as a packaged version
including hard copy documentation and support for about $700 (development license) or $1000
(deployment license) from Lutris Technologies, Inc.
A major downside of Enhydra has been its lack of support for the Java 2 Enterprise Edition. This
problem is currently being addressed: A beta version of Enhydra Enterprise has recently
become available (end of March 2001). Enhydra Enterprise will fully support J2EE.