用上转型对象实现计算矩形和圆形的周长和面积的程序

好的，这是一个关于编程的问题，我会尽力回答。使用Java语言，可以定义一个抽象的Shape类，矩形类和圆形类都继承Shape类，并实现计算周长和面积的方法。定义一个计算类，传入Shape类的实例，根据实例的类型调用相应的方法，计算出周长和面积。关于具体的代码实现，请参考下面的示例：

abstract class Shape {
    public abstract double getPerimeter();
    public abstract double getArea();
}

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

class Circle extends Shape {
    private double radius;
    public Circle(double radius) {
        this.radius = radius;
    }
    public double getPerimeter() {
        return 2 * Math.PI * radius;
    }
    public double getArea() {
        return Math.PI * radius * radius;
    }
}

class Calculator {
    public void calculate(Shape shape) {
        double perimeter = shape.getPerimeter();
        double area = shape.getArea();
        System.out.println("Perimeter: " + perimeter);
        System.out.println("Area: " + area);
    }
}

public class Main {
    public static void main(String[] args) {
        Calculator calculator = new Calculator();
        Shape rect = new Rectangle(2, 4);
        Shape circle = new Circle(5);
        calculator.calculate(rect);
        calculator.calculate(circle);
    }
}

希望对您有帮助。