JAVA学习--多态使用的一个例子

 1 public class TestAnimal {
 2     public static void main(String[] args) {
 3         TestAnimal t = new TestAnimal();
 4         t.func(new Animal());
 5         t.func(new Dog());
 6         
 7         t.func(new Cat());
 8         
 9     }
10     public void func(Animal a){//Animal a = new Dog();
11         a.eat();
12         a.jump();
13         
14         if(a instanceof Dog){
15             Dog d = (Dog)a;
16             d.Wang();
17         }
18         if(a instanceof Cat){
19             Cat c = (Cat)a;
20             c.catchMouse();
21         }
22     }
23 //    public void func(Dog a){
24 //        a.eat();
25 //        a.jump();
26 //    }
27 }
28 class Animal{
29     String name;
30     int age;
31     
32     public void eat(){
33         System.out.println("进食");
34     }
35     public void jump(){
36         System.out.println("跳");
37     }
38 }
39 class Dog extends Animal{
40     public void eat(){
41         System.out.println("狗吃食");
42     }
43     public void jump(){
44         System.out.println("狗急跳墙");
45     }
46     
47     public void Wang(){
48         System.out.println("汪汪叫");
49     }
50 }
51 
52 class Cat extends Animal{
53     public void eat(){
54         System.out.println("猫吃鱼");
55     }
56     public void jump(){
57         System.out.println("猫跳");
58     }
59     public void catchMouse(){
60         System.out.println("猫抓老鼠");
61     }
62 }