다형성

코드 내용

package Pack01;

 

class AA {

int num = 30;

 

int run() {

System.out.print("AA run");

return num;

 

}

}

 

class BB extends AA {

int num =20;

AA aa;

BB(AA aa){

this.aa = aa;

}

int run() {

System.out.println("BB run ");

return num+aa.run();

}

}

 

 

class CC extends AA {

int num =10;

AA aa;

CC(AA aa){

this.aa = aa;

}

int run() {

System.out.println("CC run ");

return num+aa.run();

}

 

}

 

 

 

 

public class Hello {

public static void main(String[] args) {

System.out.println(1);

 

AA aa = new AA();

aa = new BB(aa);

//System.out.println();

//aa.run();

aa = new CC(aa);

 

aa.run();

}

}

 

 

코드 결과화면

1

CC run

BB run

AA run