Java面向对象作业-用接口方式测试向下转型

 1 package com.java1234.chap03.sec13;
 2  
 3 public class Test2 {
 4  
 5     public static void main(String[] args) {
 6         People p1=new Student();
 7         p1.say();
 8          
 9         Student student=(Student) p1;
10         student.say();
11          
12         Teacher teacher=(Teacher) p1;
13         teacher.say();
14     }
15 }