public class Test
{
public static void main(String[] args)
{
Animal animal=new Cat();
Cat cat=animal;//会在编译错误
cat.sing();
Animal animal=new Animal();
Cat cat=(Cat)animal;//会在执行错误
cat.sing();
Animal animal=new Cat();
Cat cat=(Cat)animal;
cat.sing();
}
}
class Animal
{
public void sing()
{
System.out.println("Animal");
}
}
class Cat extends Animal
{
public void sing()
{
System.out.println("cat");
}
}
多态
最新推荐文章于 2022-05-09 14:57:00 发布