Substance look and feel

Hi...i am a java student not an expert, and need ed some help ..i am using substance for my application but am importing the substance jar in my project and putting client properties in it to use it. I would like to use substance without putting the client properties. I would like to keep my application code seperate to the substance code. If I use client property, then i wouldnt be able to compile the code unless I import the substance jar. Is there a way so that all the client properties could be set in a seperate file such as xml. And the user can change the settings in the xml file that would be seperate from the code. If the user doesnt wants to use substance look and feel, he could do it through xml file or properties file. This will help my application to run with or without substance and without accessing the main java source code. The only access of user wil be an aml or a simillar file. if you could help me...it would be great, any information on this is welcome...thanks in advance....

If you are not an expert, I recommend avoiding look-and-feel diversity.
Look-and-feel is an enormous rabbit hole to fall down and get lost in.
Design your application with one appearance and concentrate on functionality.

It is important to design a look-and-feel that can be used naturally.
A corollary is to NOT allow the user to tinker with the look-and-feel;
as a non-expert, the user can only muck up the interface.