A RemoteWebDriver could be instantiated via browsername like "firefox" via DesiredCapabilties object.

But how to get a local driver like "FireFoxDriver" with browser name?

My use case is as follows: the browsers to be tested are specified via properties in an external text file. with another property the grid url is set. if grid url is set to "local" i want to run the tests local on the browsers set in text file. 

(how) is this possible?