public class Main {
private static String OS = System.getProperty("os.name").toLowerCase();
public static void main(String[] args) {
    System.out.println(OS);
    try {
        System.out.println(java.net.Inet4Address.getLocalHost().getHostAddress());
    }
    catch(java.net.UnknownHostException e) {
        System.out.println(e.getStackTrace().toString());
    }
}
}