Pass path from EnsLib.HL7.Service.FTPService to EnsLib.HL7.MsgRouter.RoutingEngine?

I have a service named FTP_In that is of class EnsLib.HL7.Service.FTPService.   It picks up files from multiple subfolders and sends them to an EnsLib.HL7.MsgRouter.RoutingEngine.   What I want to do is somehow capture the subfolder as a variable for use in the routing rules.  Is this possible?

Let's say I have the following files and directory structure on my FTP Server

I want the Routing Rule to be able to send anything that came from the /green/ folder to one operation and from /yellow/ to another.