Сколько тебе лет

public class JavaAge {
    public static void main(String[] args) {
        int javaReleaseYear = 1996;
        int currentYear = java.util.Calendar.getInstance().get(java.util.Calendar.YEAR);
        System.out.println("Java is " + (currentYear - javaReleaseYear) + " years old!");
    }
}