I was wondering what is the "recommended" way of handling the situation where a web application refers to an external file? HOWEVER I do not want to alter the WAR file if possible after deployment (as its produced by another party).

This is one suggested way, which works for Tomcat but doesn't seem to work easily for other appservers (including JBoss):
* Look up an environment variable (using JNDI) which specifies the name of the file. If that can't be found, use a context parameter from the web.xml.
* Deploy an additional file which specifies the value of this environment variable.

I'm unsure how to do something similar in JBoss as above (can't seem to find it in the documentation).

Can somebody either:
1. Tell me how to do this in JBoss - specify any environment variables outside the WAR/EAR file (like the descriptor file you put in the webapp directory of a raw Tomcat installation), OR
2. Suggest a different way to solve this problem, particularly if it is portable to other application servers.

Thanks,

Ian