Here is a good tutorial regarding, setting the class path. Further you might like to read Managing the Java classpath (Windows).
Having said that, you should not set the classpath for your driver in Windows environment variable. Instead, you should include that driver jar
inside your IDE under project properties. But I noticed that you are actually using Maven. In this case you should look for the driver under Maven in order to fulfil that dependency. Maven will download the driver jar, if doesn’t exist, and make it local.
In case, you are not using any IDE, then you can create a lib
directory and tell the compiler that all required jar
s are in there, at the time of compilation/execution. You can find HOW, in the former link given above.