It's not directly possible in Java because the language is not that low-level. If you want machine-specific information, you'll need to either obtain or write yourself some native code and make the necessary calls through JNI (Java Native Interface). It allows you to make platform-specific native calls so that you can retrieve the type of information you're looking for.
Google for JNI for a nice tutorial by sun
Dad always thought laughter was the best medicine, which I guess is why several of us died of tuberculosis. -Jack Handy