我想介绍一个Shape类作为类父接口Circle和Rectangle。我必须实现getName()将Circle为该Circle对象和Rectangle该Rectangle对象返回的方法。另外，我必须toString()在Circle和Rectangle类中都覆盖该方法。这些toString方法将调用该getName()方法，并将生成一个表示对象的字符串，如下所示：

• Circle 半径为2的表示为 "Circle(2)"
• Rectangle宽度为2且高度为10的表示为"Rectangle(2, 10)"。

此外，我不能修改的类Shape，Rectangle，Circle或者Main，为此你会发现下面的代码。我不确定如何执行此操作。有人可以帮帮我吗？

到目前为止，这是我所做的：

Shape.java

public interface Shape {
    String getName();
    double getPerimeter();
    double getArea();
}

Rectangle.java

public class Rectangle {
    private double width, height;
    public Rectangle(double width, double height) {
        this.width = width;
        this.height = height;
    }
    public double getPerimeter() {
        return 2 * (this.width + this.height);
    }
    public double getArea() {
        return this.width * this.height;
    }
}

Circle.java

public class Circle{
    private double radius;
    public Circle(double radius) {
        this.radius = radius;
    }
    public double getPerimeter() {
        return 2 * Math.PI * this.radius;
    }
    public double getArea() {
        throw new RuntimeException("Oops, I don't know how to calculate this :(");
    }
}

问题

public aspect Question {
    declare parents: Rectangle implements Shape;
    declare parents: Circle implements Shape;
    
    public String Rectangle.getName(){
        return "Rectangle";
    }
    
    public String Circle.getName(){
        return "Circle";
    }
    
    public String Rectangle.toString(){
        return Rectangle.getName()+"(" + this.width +", " + this.height +")";
    }
    
    public String Circle.toString(){
        return Circle.getName() + "(" + this.radius + ")";
    }
}

Main.java

public class Main {
    public static void main(String[] args) {
        try {
            Shape s;
            s = (Shape) new Rectangle(2, 10);
            System.out.println("The area of " + s + " is " + s.getArea());
            s = (Shape) new Rectangle(-2, 10);
            System.out.println("The perimeter of " + s + " is " + s.getPerimeter());
            s = (Shape) new Circle(-2);
            System.out.println("The perimeter of " + s + " is " + s.getPerimeter());
            s = (Shape) new Circle(2);
            System.out.println("The area of " + s + " is " + s.getArea());
        }
        catch(Exception e) {
            System.out.println("Error: " + e.getMessage());
        }
    }
}