public class Boss ???????????????????? {
    public int count;

    public Boss() {
        count = 0;
    }

    @Override
    public void attack(Player p) {
        System.out.print("Boss の攻撃: ");
        if (++count >= 3) {
            p.damage(1000);
        } else {
            p.damage(0);
        }
    }
}