java bPoint.x 这样用可以吗
public class Point{

private long x ;
private long y ;

public Point(long x ,long y){
this.x = x ;
this.y = y ;
}
}
class Graphics{

public long perimeter() ;
public long area() ;
}

class Rectangle extends Graphics{
private Point bPoint ;
private Point ePoint ;

public Rectangle(){}
public Rectangle(Point bPoint, Point ePoint){
this.bPoint = bPoint ;
this.ePoint = ePoint ;
}

public long perimeter() {
return (Math.abs(bPoint.x-ePoint.x)+Math.abs(bPoint.y-

ePoint.y))*2;
}
public long area() {
return Math.abs(bPoint.x-ePoint.x)*Math.abs(bPoint.y-

ePoint.y);
}
}
public class PassTest3{
public static void main(String[] args){
Graphics g = new Rectangle(new Point(0, 1), new Point(5,5));
System.out.println(g.area() + "----" + g.perimeter());
}
}

[解决办法]
不可以 私有属性不能直接访问，你可以通过getter/setter方法访问