java - 不能从静态上下文中引用非静态方法 toString()

Question

不需要任何代码，只需要某种指导。想保持我的学术诚信；)

我一直收到那个烦人的错误。我需要为每个 Room 实例调用 toString 方法。有什么建议么？如果可能的话，我希望在 2 小时内得到答复。

public class Hotel
{
    //constant
    public static final int NUM_ROOMS = 20;

    //variables
    public Room[] theRoom;
    public String name;
    public int totalDays;
    public double totalRate;
    public int singleCount;
    public int doubleCount;
    public int roomsRented;
    public int NOT_FOUND;

    public Hotel(String newName) {
        name = newName;
        Room[] Rooms = new Room[NUM_ROOMS];
    }

    public double getTotalRentalSales() {
        return totalRate + roomsRented;
    }

    public double getAvgDays() {
        return roomsRented/totalDays;
    }

    public double getAvgRate() {
        return totalRate/roomsRented;
    }

    public int getSingleCount() {
        return singleCount;
    }

    public int getDoubleCount() {
        return doubleCount;
    }

    public String printRentalList() {
        System.out.println("Room Information: " + Room.toString());
    }
}

Answer 1

您不应尝试在 Room 类上调用 toString()，而应在 Room 对象 上调用。在该方法中，使用 for 循环遍历房间数组，并打印通过为数组中保存的每个 Room 对象调用 toString() 返回的字符串，因为这看起来像您的方法应该做的.

例如

System.out.println("All Foos held here include: ");

// using a "for-each" loop, assuming an array called fooArray that holds Foo objects
for (Foo foo: fooArray) {
   System.out.println(foo);
}

您显然必须更改代码的类型和变量名称。

编辑 2:虽然您必须使用标准的 for 循环，而不是 for-each 循环，因为您不会遍历整个数组，而是在达到 roomsRented 计数时退出。

System.out.println("All Foos held here include: ");

// using standard for loop, assuming an array called fooArray that holds Foo objects
for (int i = 0; i < someMaxNumber; i++) {
   System.out.println(fooArray[i]);
}