class Point{ private double x; private double y; Point(double x1,double y1){ x=x1; y=y1; } public

class Point{ private double x; private double y; Point(double x1,double y1){ x=x1; y=y1; } public
class Point{ private double x; private double y; Point(double x1,double y1){ x=x1; y=y1; } public

class Point{ private double x; private double y; Point(double x1,double y1){ x=x1; y=y1; } public
class Point {
private double x; //3.x坐标
private double y; //4.y坐标
Point(double x1,double y1) {
x = x1;
y = y1;
}
Point(){ //2.增加默认构造函数Point()
}
public double getX()
public double getY()
public void setX(double i)
public void setY(double i)
}
class fatherCircle extends Point{
protected Point o;//6.权限由private 改为protected,对子类可视 //圆点
protected double radius;//8.权限由private 改为protected,对子类可视 //半径
fatherCircle(Point p,double r){
o = p;
//r=1.0; //9.这句没用,去掉
radius = r;
}
fatherCircle(Point p){ //10.增加构造函数fatherCircle(Point p)
this(p,1.0);
}
fatherCircle(){ //7.增加默认构造函数fatherCircle()
}
public double area() { //13.增加方法计算面积
return 3.14 * radius * radius;
}
}
class sunCircle extends fatherCircle{ //3去掉public,一个类文件中只能存在一个public类文件
sunCircle(Point p,double r){ //11.增加构造函数sunCircle(Point p,double r)
super(p,r);
}
public void setO(double x,double y){ //设置圆点坐标
o.setX(x);
o.setY(y);
}
public Point getO() //取圆点
public double getRadius(){ //取半径//9.去掉参数
//radius.setR(r); //9.去掉这句
return radius;
}
public void setRadius(double r) //设半径
public double area() { //计算面积
return 3.14 * radius * radius;
}}
public class circles{
public static void main(String[] args){//1.string改为String
fatherCircle fatherObject = new fatherCircle(new Point(1.0,2.0));
sunCircle sunObject =new sunCircle(new Point(2.0,1.0),1.0);
System.out.println("fatherObject area="+fatherObject.area());//12.pointln改为println
System.out.println("sunObject radius="+sunObject.getRadius());//12.pointln改为println
System.out.println("sunObject area="+sunObject.area());//12.pointln改为println
}
}
改动的地方都用数字标示了,拷出来就可以直接运行了,改成这样,不知道你满意不?