java - 方法 toString() 问题

Question

我正在创建食堂管理应用程序。我必须在某处使用覆盖方法 toString()，所以我将它放在 Menu 类中以显示菜单总价格。但我不能在我的 main() 中调用该方法。我怎样才能做到这一点 ？

class Menu {

    private Soup soup;
    private SecondMeal second;
    private Dessert desert;

    public Menu(int soupId, int secId, int desId) {
        soup = new Soup(soupId);
        second = new SecondMeal(secId);
        desert = new Dessert(desId);
    }

    double price = soup.getPrice() + second.getPrice() + desert.getPrice();

    //here is my toString() method
    @Override
    public String toString() {
        String str = "Your menu price is " + price;
        return str;
    }

}

public class Testing {

    public static void main(String [] args) throws FileNotFoundException {

        Scanner scan = new Scanner(System.in);
        int soupId, secondId, desertId;

        do {
            System.out.println("Choose soup: ");
            Display.soupMenu();
            soupId = scan.nextInt();
        }
        while (soupId < 1 || soupId > 3);

        do {
            System.out.println("Choose second meal: ");
            Display.secondMenu();
            secondId = scan.nextInt();

        }
        while (secondId < 1 || secondId > 3);

        do {
            System.out.println("Choose dessert: ");
            Display.desertMenu();
            desertId = scan.nextInt();

        }
        while (desertId < 1 || desertId > 3);

        // here is the problem...
        System.out.println(Menu.toString()); // cannot make a static reference to the non-static method

    }
}

Answer 1

您必须创建一个 Menu 实例并对其调用“toString())”，因为它不是静态的。