SSI (Server Side Includes) are directives that are placed in HTML pages,
and evaluated on the server while the pages are being served. They let you
add dynamically generated content to an existing HTML page, without having
to serve the entire page via a CGI program, or other dynamic technology.
Within Tomcat SSI support can be added when using Tomcat as your
HTTP server and you require SSI support. Typically this is done
during development when you don't want to run a web server like Apache.
Tomcat SSI support implements the same SSI directives as Apache. See the
Apache Introduction to SSI for information on using SSI directives.
SSI support is implemented using the servlet class
org.apache.catalina.ssi.SSIServlet. Traditionally, this servlet
is mapped to the URL pattern "*.shtml".
By default SSI support is disabled in Tomcat.