Howdy Akshay, we don't have a lot of rules at the Ranch, but one we do have is to have names, both first and last, that are obviously not fictitious. It doesn't have to be your real last name, just something better than "xyz"
Click on the "My Profile" link and change it.
As far as your question goes, I haven't found anything in the Java I/O classes that would give you this information. There may be some 3rd party package that would allow this, but I don't think it is possible with the standard API.