o****i
发帖数: 1706 | 1 作业，里面有一个要求父类实例调用子类的方法..call a Cylinder method on a
Circle，不知道怎么搞，代码如下，谢谢大家..：
import java.text.*;
public class Circle {
DecimalFormat format=new DecimalFormat("#,###.00");
final double PI=3.1415926536;
double radius=0;
public Circle(){
radius=0;
}
public Circle(double r){
radius=r;
}
public void setRadius(double r){
radius=r;
}
public double getRadius(){
return radius;
}
public String toString(){
return "Radi | s***8
发帖数: 1136 | 2 you can't.
the last stmt won't compile
More importantly, I don't see a reasonable is-a relationship between the two
. Maybe has-a relationship? |
|
