鸟类都会飞么

class Bird {
public void fly() {
System.out.println("鸟类都会飞么？");
}
}
public class Chicken extends Bird {
@Override
public void fly() {
System.out.println("鸡就不会飞！");
}
public static void main(String[] args) {
Chicken chicken = new Chicken();
System.out.println("鸡是否属于鸟类？");
if (chicken instanceof Bird) {
System.out.println("鸡属于鸟类。");
Bird bird = new Bird();
bird.fly();
chicken.fly();
} else {
System.out.println("鸡不属于鸟类！！！");
}
}
}