The Tomcat story

Meanwhile, an external group of open-source developers were working on a JSP/servlet engine that was compatible with the latest servlet and JSP APIs but would work with the widely used Apache server. The group was known as the Apache Java group, and its JSP/servlet engine was called Apache JServ. They wrote JServ in a two-part implementation: one part was a C-based implementation that was a loadable module for the Apache server; the other part was a stand-alone Java implementation of the servlet engine. The two parts communicate using a private protocol. While the design of Sun's JSDK reference was focused on compliance to specifications, the Apache JServ engine was focused on delivering high performance and other more pragmatic production issues.

It soon became obvious that there was quite a lot of overlap between the two major development efforts. Many users wanted to work with the Sun reference implementation for production use, but were frustrated with performance roadblocks. Meanwhile, Apache JServ users were demanding closer adherence to reference standards and faster tracking to the latest and greatest servlet and JSP specifications. It became apparent that the two efforts should merge.

In 1999 Sun donated the source code of the servlet and JSP reference engine implementations to the Apache Software Foundation (ASF). A collaborative subgroup called the Jakarta project was formed to focus on the servlet and JSP engines and merging the Sun reference implementation technology and the Apache JServ technology. But the project ended up handling all of the projects formerly under the auspices of the Apache Java group. All of the projects under the Jakarta umbrella are Java language open-source projects supporting the Apache Software License. Tomcat is one of those projects.

The Tomcat project charter is to provide an official reference implementation for the latest servlet and JSP specifications. The progeny of Sun's reference implementations eventually became the Tomcat 3.x series of products under Jakarta and implemented the JSP 1.1 and Servlet 2.2 API specification. Tomcat 4.x, the first release to employ the new integrated, high-performance architecture, will serve as the reference implementation for the JSP 1.2 and Servlet 2.3 API specification.

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