java - 设计问题 : Reservation system

Question

我必须为酒店设计和实现预订系统。我有

• 预订对象的数组列表
• 房间对象的数组列表

我想在指定日期“预订”房间。

预订没有日期的房间很容易，但日期部分却让事情变得复杂。我正在为此设计而苦苦挣扎，并且有信心朝着正确的方向轻推我可以对其进行编码。

怎么说一个房间在这个日期被预订但那个日期没有？

没有数据库或任何东西，它只是一个抽象的预订系统。

(我已经盯着这个看了一段时间，如果解决方案很简单，请原谅我)

谢谢。

Answer 1

创建三个类(Hotel、Room & Reservation):

• Reservation 对象在这里用作发票，并且与预订流程分离。

• 每个 Room 对象(专用于酒店中的每个房间号)都包含一个 map，它存储 reservedDates 作为键和 reservationObject 作为值。

• 酒店由房间组成。对于每个预订请求，Hotel 循环遍历 room 列表，每个 room 遍历自己的 map 查找是否可以预订要求 天。

请注意，预订功能将日期作为列表，而不仅仅是两个日期(如开始日期和结束日期)。这与前者可以从后者推导出来是一样的。

示例代码如下:

class Hotel {
    private String name, address;
    private List<Room> roomList;   //key : roomNumber
    public Hotel(){
        roomList = new ArrayList<Room>();
    }
    public Reservation bookRoomForDates(List<Integer> dateList, Guest guest){
        for(Room room : roomList){
            Reservation reservation = room.bookForGivenDates(dateList, guest);
            if(reserved != null) return reservation; //Reservation successFull!
        }
        return null; //Reservation failed!
    }
}
class Reservation {
    private String id;
    private Date inDate, outDate;
    private Guest guest;

    public Reservation(Room room, int startDate, int endDate, Guest guest){
        //populate the member variables.
    }
}

class Room {
    private String id;
    private int roomNumber, floorNum;
    private Map<Integer, Reservation> reservedDates;  // key : date as Integer (YYYYMMDD)

    public Room(int roomNumber){
        reservedDates = new HashMap<Integer, Reservation>();
        this.roomNumber = roomNumber;
    }

    //A guest request for booking on dates(in YYYYMMDD format) in the dateList
    public Reservation bookForGivenDates(List<Integer> dateList, Guest guest)  
    {   
        if(dateList.isEmpty()) return null;

        for(Integer date : dateList){
            Reservation res = reservedDates.get(date);  
            if(res != null) {  // We don't store null value for unreserved dates for the room.
                return null;  // Room is reserved on this date by another guest. So, this room is unavailable.
            }
        }
        //this room is unreserved on all requested dates. So go on and reserve this room for asked dates
        int startDate = dateList.get(0);
        int endDate   = dateList.get(dateList.size() - 1);

        Reservation newReservation = new Reservation(this, startDate, endDate, guest);
        for(Integer date : dateList){
            reservedDates.put(date, newReservation);
        }
        return newReservation;
    }
}