用JAVA写一个机票预定系统

好的，以下是一个简单的机票预定系统的Java代码示例：

import java.util.Scanner;

public class TicketReservationSystem {
    
    // 定义常量
    private static final int MAX_SEATS = 50;
    private static final double BASE_PRICE = 100.0;
    private static final double VIP_PRICE = 200.0;
    
    // 定义数组
    private static String[] passengerNames = new String[MAX_SEATS];
    private static boolean[] isVIPs = new boolean[MAX_SEATS];
    private static double[] ticketPrices = new double[MAX_SEATS];
    
    // 定义变量
    private static int numSeatsSold = 0;
    private static double totalRevenue = 0.0;
    
    public static void main(String[] args) {
        
        Scanner scanner = new Scanner(System.in);
        
        // 显示菜单
        System.out.println("Welcome to the Ticket Reservation System!");
        System.out.println("1. Book a seat");
        System.out.println("2. Cancel a booking");
        System.out.println("3. View bookings");
        System.out.println("4. Quit");
        
        // 处理用户输入
        boolean quit = false;
        while (!quit) {
            System.out.print("Please enter your choice: ");
            int choice = scanner.nextInt();
            
            switch (choice) {
                case 1:
                    bookSeat();
                    break;
                case 2:
                    cancelBooking();
                    break;
                case 3:
                    viewBookings();
                    break;
                case 4:
                    quit = true;
                    break;
                default:
                    System.out.println("Invalid choice. Please try again.");
                    break;
            }
        }
        
        // 关闭scanner
        scanner.close();
    }
    
    // 预定座位
    private static void bookSeat() {
        
        Scanner scanner = new Scanner(System.in);
        
        // 检查是否还有座位
        if (numSeatsSold >= MAX_SEATS) {
            System.out.println("Sorry, all seats have been sold.");
            return;
        }
        
        // 获取乘客姓名
        System.out.print("Please enter your name: ");
        String name = scanner.nextLine();
        
        // 判断是否为VIP乘客
        System.out.print("Are you a VIP passenger? (y/n): ");
        String vipInput = scanner.nextLine();
        boolean isVIP = vipInput.equalsIgnoreCase("y");
        
        // 计算票价
        double ticketPrice = isVIP ? VIP_PRICE : BASE_PRICE;
        
        // 显示座位号和票价
        int seatNumber = numSeatsSold + 1;
        System.out.printf("Seat number: %d\n", seatNumber);
        System.out.printf("Ticket price: %.2f\n", ticketPrice);
        
        // 存储预定信息
        passengerNames[numSeatsSold] = name;
        isVIPs[numSeatsSold] = isVIP;
        ticketPrices[numSeatsSold] = ticketPrice;
        numSeatsSold++;
        totalRevenue += ticketPrice;
        
        // 关闭scanner
        scanner.close();
    }
    
    // 取消预定
    private static void cancelBooking() {
        
        Scanner scanner = new Scanner(System.in);
        
        // 获取要取消预定的座位号
        System.out.print("Please enter the seat number you want to cancel: ");
        int seatNumber = scanner.nextInt();
        
        // 检查座位号是否合法
        if (seatNumber <= 0 || seatNumber > numSeatsSold) {
            System.out.println("Invalid seat number. Please try again.");
            return;
        }
        
        // 获取票价
        double ticketPrice = ticketPrices[seatNumber - 1];
        
        // 显示取消预定信息
        System.out.println("Booking cancelled.");
        System.out.printf("Passenger name: %s\n", passengerNames[seatNumber - 1]);
        System.out.printf("Ticket price: %.2f\n", ticketPrice);
        
        // 移除预定信息
        for (int i = seatNumber - 1; i < numSeatsSold - 1; i++) {
            passengerNames[i] = passengerNames[i + 1];
            isVIPs[i] = isVIPs[i + 1];
            ticketPrices[i] = ticketPrices[i + 1];
        }
        passengerNames[numSeatsSold - 1] = null;
        isVIPs[numSeatsSold - 1] = false;
        ticketPrices[numSeatsSold - 1] = 0.0;
        numSeatsSold--;
        totalRevenue -= ticketPrice;
        
        // 关闭scanner
        scanner.close();
    }
    
    // 查看预定信息
    private static void viewBookings() {
        
        // 检查是否有预定信息
        if (numSeatsSold == 0) {
            System.out.println("No bookings found.");
            return;
        }
        
        // 显示预定信息
        System.out.println("Seat  Passenger Name  VIP  Ticket Price");
        for (int i = 0; i < numSeatsSold; i++) {
            System.out.printf("%-5d %-14s %-4s %.2f\n", i + 1, passengerNames[i], isVIPs[i] ? "Yes" : "No", ticketPrices[i]);
        }
        System.out.printf("Total revenue: %.2f\n", totalRevenue);
    }
}

上述代码实现了以下功能：

1. 显示菜单，让用户选择操作；
2. 预定座位，包括获取乘客姓名、判断是否为VIP乘客、计算票价、显示座位号和票价，以及存储预定信息；
3. 取消预定，包括获取要取消预定的座位号、检查座位号是否合法、获取票价、显示取消预定信息，以及移除预定信息；
4. 查看预定信息，包括显示座位号、乘客姓名、是否为VIP乘客和票价，以及显示总收入。

当然，这只是一个简单的示例代码，实际的机票预定系统需要考虑更多的因素，如航班、舱位、座位等级等。