1-21作业2

1

 1 package kslx.zuoye.zuoye02;
 2 
 3 public class Test {
 4     public static void main(String[] args){
 5         
 6         Pet dog=new Dog();
 7         if(dog instanceof Dog) {
 8             ((Dog) dog).diao();
 9         }else if(dog instanceof Pen){
10             ((Pen) dog).youyong();
11         }
12 
13 
14 
15     }
16 }

2

 1 package kslx.zuoye.zuoye02;
 2 
 3 public abstract class Pet {
 4     private String name;
 5 
 6     public int getHealth() {
 7         return health;
 8     }
 9 
10     public void setHealth(int health) {
11         this.health = health;
12     }
13 
14     private int health;
15     public String getName() {
16         return name;
17     }
18 
19     public void setName(String name) {
20         this.name = name;
21     }
22 
23     public  void wan(){}
24 }

3

1 package kslx.zuoye.zuoye02;
2 
3 public class Pen extends Pet {
4 
5     public void youyong() {
6         System.out.println("南极游泳");
7 
8     }
9 }

4

1 package kslx.zuoye.zuoye02;
2 
3 public class Dog extends Pet {
4 
5     public void diao() {
6         System.out.println("叼飞碟...");
7     }
8 }

5