package com.cn.test9;
public class RTTI {
/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
Useful[] x={
new Useful(),
new MoreUseful()
};
x[0].f();
x[1].g();
((MoreUseful)x[1]).u();//向上转型不一定安全
}
}
class Useful{
public void f(){
System.out.println("Useful f");
}
public void g(){
System.out.println("Useful haha");
}
}
class MoreUseful extends Useful{
public void f(){
System.out.println("MoreUseful haha");
}
public void g(){
System.out.println("MoreUseful g");
}
public void u(){
System.out.println("heihie");
}
public void v(){
}
public void w(){
}
}
RTTI
最新推荐文章于 2021-08-31 22:41:37 发布