private static void newJavaWay() {
        Collections.sort(users,(User u1, User u2) -> u1.id.compareTo(u2.id));
        printListNewWay("by ID");

        Collections.sort(users, (User u1, User u2) -> u1.firstName.compareTo(u2.firstName));
        printListNewWay("by FirstName");

        Collections.sort(users, (User u1, User u2) -> u1.lastName.compareTo(u2.lastName));
        printListNewWay("by LastName");

        Collections.sort(users, (User u1, User u2) -> u1.age.compareTo(u2.age));
        printListNewWay("by Age");

    }