public class Dog extends Animal implements Swimmable {

    // 重写父类抽象方法：发出叫声
    @Override
    public void makeSound() {
        System.out.println("汪汪汪！");
    }

    // 实现接口的swim方法
    @Override
    public void swim() {
        System.out.println("小狗在水里游泳~");
    }
}