I agree, its a bit odd, I just didn't have the time to investigate at this point and figured someone put the comment there perhaps thinking there might be an argument that was "null" was ok.  One thing I thought of was if one of the args is null, like the hostname or masterAddress, if you just strip it out, then the usage is wrong and it might not be obvious why its failing. Hopefully it would complain somewhere on startup that a null was passed and it would be easier to debug.