java面向对象之父类的引用指向子类的对象

1 package Text;
2 
3 public class Job {
4     public void dowork(){
5         
6     }
7 }
1 package Text;
2 
3 public class Luosidao extends Job{
4     public void dowork(){
5         System.out.println("螺丝刀拧螺丝。。。");
6     }
7 }
 1 package Text;
 2 
 3 public class Chanzi extends Job{
 4 
 5     @Override
 6     public void dowork() {
 7         System.out.println("铲子铲土。。。");
 8     }
 9     
10     public void test(){
11         System.out.println("测试方法");
12     }
13 }
 1 package Tool;
 2 
 3 import Text.Chanzi;
 4 import Text.Job;
 5 import Text.Luosidao;
 6 
 7 public class Tool3 {
 8     public static void main(String[] args) {
 9         Job a =new Luosidao();
10         Job b =new Chanzi();
11         a.dowork();
12         b.dowork();
13         Chanzi c =(Chanzi)b;//无法调用子类方法,所以强转
14         c.test();
15     }
16 }

 

posted on 2017-07-20 16:58  为伊消得  阅读(134)  评论(0编辑  收藏  举报