Runtime Class
This is a class in Java you can use to grab the Runtime Environment of the machine where the Java Program is running. You can use this among other things to execute operating system commands or scripts.
The process is:
Example using a Servlet (yes, we have not gone over Servlets but, look at the steps inside of the code, you could easily put it in the main method of your application). This code simply gets a filelisting of a certain directory