I have a basic web application packaged as an EAR deployed on GlassFish. The web module has some html files. The html files have a common footer, an html file, that I would like to extract out and make an include. When I do, and put:
<!--#include virtual="insertthisfile.html" -->
in an html file, it does not work. Should this work?
This is a technique called Server-Side Includes (SSI). It may not be enabled on your web host. If it is, sometimes they force a .shtml extension to be required for included files, so try renaming your file insertthisfile.shtml.
If that doesn't work, you might be able to enable SSIs in a .htaccess file (assuming your web server is Apache). You can find instructions on how to do this by googling. There's a decent set here.
If that fails, I would contact your web host and see if they have SSIs enabled.