단일상속 extends Object & 접근지정자 protected & super,this

import java.lang.*; // 생략된 형태

class AA extends Object{
 int x = 100;
 }

class BB extends AA{
 int y = 200;
}

class CC extends BB{
 int z = 300;
}

public class object extends Object{
 public static void main(String arg[]){
  CC cp = new CC();
  System.out.println("z ="+cp.z);
  System.out.println("y ="+cp.y);
  System.out.println("x ="+cp.x);
 }
}

=================================================================================

//접근 지정자 protected
class AA{
 protected int x = 100;
 protected int y = 200;
 public void disp(){
  System.out.println("x= "+x);
  System.out.println("y= "+y);
 }
}

class BB extends AA{
 private int z = 300;
 public void disp_BB(){
  System.out.println("x= "+x);
  System.out.println("y= "+y);
  System.out.println("z= "+z);
 }
}

public class object extends Object{
 public static void main(String arg[]){
  BB bp = new BB();
  bp.disp_BB();
 }
}

=================================================================================
// 상속 super, this
class AA{
 protected int x = 100;
 protected int y = 200;
 }

class BB extends AA{
 private int x = 300;
 private int y = 400;
 public void disp_BB(){
  System.out.println("x= "+this.x);
  System.out.println("y= "+super.y);
 }
}

public class object extends Object{
 public static void main(String arg[]){
  BB bp = new BB();
  bp.disp_BB();
 }
}


//다중상속
http://kin.naver.com/db/detail.php?d1id=1&dir_id=10106&eid=6OlzAj11jEBC69nMnZgli5VhEzzUi25A&qb=tNzAz7vzvNM=