홍대 자바 수업 상속 .만약 슈퍼 클래스에 디폴트 생성자없으면 이렇게

class Point2D
{
	protected int x=10;
	protected int y=20;
	

	public Point2D(int xx,int yy)
	{
	   x=xx ; y=yy;
	}

}

class Point3D extends Point2D{
	protected int z=30;
	public void print(){
		System.out.println(x+" "+" "+y+" "+z);
	}
	public Point3D(){
		super(123,456);
		System.out.println("서브 클래스 생성자 호출");

	}
	public Point3D(int xx,int yy,int zz)
	{
		super(xx,yy);
	   x=xx ; y=yy; z=zz;
	}

	
}
class Noname1
	{
	public static void main (String [] args)
		{
			Point3D pt=new Point3D();
			pt.print();
			Point3D pt2=new Point3D(1,2,3);
			pt2.print();
		}

	}