package chapter4.demo45;

/**
 * 图形计算器类
 * 1. final 类：防止被继承
 * 2. 私有构造函数（不可被实例化）
 * 只有静态方法，不需要实例化，所有方法都可以通过类名调用
 */
public final class ShapeCalculate {
    private ShapeCalculate() {
        throw new AssertionError("不应该被实例化");
    }

    // 打印图形面积
    public static void printArea(Shape shape) {
        if (shape instanceof Rectangle) {
            System.out.println("正方形面积："+shape.getArea());
        } else if (shape instanceof Circle) {
            System.out.println("圆形面积："+shape.getArea());
        } else {
            System.out.println("未知图形面积：" + shape.getArea());
        }
    }

    // 打印图形周长
//    public static void printPerimeter(Shape shape) {
//        if (shape instanceof Rectangle) {
//            System.out.print("长方形");
//        } else if (shape instanceof Circle) {
//            System.out.print("圆形");
//        } else {
//            System.out.print("未知图形");
//        }
//        System.out.println("周长："+shape.getPerimeter());
//    }

    public static void printPerimeter(Circle circle) {
        System.out.println("圆形周长："+circle.getPerimeter());
    }

    public static void printPerimeter(Rectangle rectangle) {
        System.out.println("长方形周长："+rectangle.getPerimeter());
    }

    // 打印计算器菜单
    public static void printMenu() {
        System.out.println("==========图形计算器==========");
        System.out.println("1.圆形");
        System.out.println("2.长方形");
        System.out.print("请输入序号选择功能：");
    }
}