java通过日历预约并设置预约人数代码实现

以下是Java日历预约并设置预约人数的示例代码：

import java.util.*;

public class CalendarBooking {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        Calendar calendar = Calendar.getInstance();
        int year, month, day, hour, minute, duration, maxAttendees;

        System.out.print("请输入预约的年份:");
        year = scanner.nextInt();
        System.out.print("请输入预约的月份:");
        month = scanner.nextInt() - 1; // Calendar.MONTH的范围是0~11
        System.out.print("请输入预约的日期:");
        day = scanner.nextInt();
        System.out.print("请输入预约的小时:");
        hour = scanner.nextInt();
        System.out.print("请输入预约的分钟:");
        minute = scanner.nextInt();
        System.out.print("请输入预约的时长(分钟):");
        duration = scanner.nextInt();
        System.out.print("请输入最大的参与人数:");
        maxAttendees = scanner.nextInt();

        calendar.set(Calendar.YEAR, year);
        calendar.set(Calendar.MONTH, month);
        calendar.set(Calendar.DAY_OF_MONTH, day);
        calendar.set(Calendar.HOUR_OF_DAY, hour);
        calendar.set(Calendar.MINUTE, minute);
        calendar.set(Calendar.SECOND, 0);
        calendar.set(Calendar.MILLISECOND, 0);

        System.out.println("开始时间:" + calendar.getTime());

        // 创建事件
        Event event = new Event(calendar, duration, maxAttendees);

        // 预约
        boolean success = event.book();

        if (success) {
            System.out.println("预约成功!");
        } else {
            System.out.println("预约失败!");
        }
    }
}

class Event {
    private final Calendar startTime;
    private final int duration; // 单位:分钟
    private final int maxAttendees;
    private final Set<String> attendees = new HashSet<>(); // 已经参加的人员

    public Event(Calendar startTime, int duration, int maxAttendees) {
        this.startTime = startTime;
        this.duration = duration;
        this.maxAttendees = maxAttendees;
    }

    // 预约
    public boolean book() {
        // 先检查是否能够参加
        if (attendees.size() < maxAttendees) {
            long startMillis = startTime.getTimeInMillis();
            long endMillis = startMillis + duration * 60 * 1000;

            // 检查时间是否冲突
            for (String attendee : attendees) {
                Set<Event> events = Attendee.getEvents(attendee);
                for (Event event : events) {
                    long eventStartMillis = event.startTime.getTimeInMillis();
                    long eventEndMillis = eventStartMillis + event.duration * 60 * 1000;
                    if (startMillis < eventEndMillis && endMillis > eventStartMillis) {
                        return false; // 时间冲突
                    }
                }
            }

            attendees.add("预约人"); // 预约人默认参加
            return true;
        } else {
            // 人数已满
            return false;
        }
    }
}

class Attendee {
    // 用来存储某人参加了哪些事件
    private static final Map<String, Set<Event>> ATTENDEE_EVENTS_MAP = new HashMap<>();

    // 获取某人参加的所有事件
    public static Set<Event> getEvents(String attendee) {
        return ATTENDEE_EVENTS_MAP.getOrDefault(attendee, new HashSet<>());
    }
}

在这段代码中，我们先创建了一个 `Calendar` 实例来表示预约的开始时间，然后输入预约的时长和最大参与人数。接下来，我们使用这些信息来创建一个 `Event` 实例，并调用 `book` 方法进行预约。如果预约成功，就会添加预约人的名字到参与名单里，否则返回错误信息。

注意，这段代码只是一个简单的示例，没有进行实际的持久化和数据校验。在实际应用中，需要根据具体需求进行设计和改进。