User of "catalina.home" property

[Anand B N]

Can we rely on the fact that catalina.home property will always return a 
valid path(either ".." a.k.a. parent or an absolute path) abd write 
components that will run for Tomcat only based on that property.

Currently I do the following:-

         FileInputStream in ;
         File catalinaHome = new  File(System.getProperty("catalina.home"));
         handlerMap = new HashMap();

         /*
           Load request mapping File descriptor
         */
         in = new 
FileInputStream(catalinaHome.getCanonicalFile()+fileSeparator+"webapps"+fileSeparator+"casadmin"......

I works fine so far but justo find out if it can be relied upon.

Anand