用java写火车订票系统，包含增删改方法，接口继承

好的，以下是一个简单的火车订票系统的Java代码示例：

// TrainTicket类，表示火车票
public class TrainTicket {
    private String trainNumber;
    private String departure;
    private String destination;
    private String date;

    public TrainTicket(String trainNumber, String departure, String destination, String date) {
        this.trainNumber = trainNumber;
        this.departure = departure;
        this.destination = destination;
        this.date = date;
    }

    // 省略getter和setter方法

    @Override
    public String toString() {
        return "TrainTicket{" +
                "trainNumber='" + trainNumber + '\'' +
                ", departure='" + departure + '\'' +
                ", destination='" + destination + '\'' +
                ", date='" + date + '\'' +
                '}';
    }
}

// TrainTicketDao接口，定义了增删改查操作
public interface TrainTicketDao {
    void addTicket(TrainTicket ticket);
    void deleteTicket(String trainNumber, String date);
    void updateTicket(TrainTicket ticket);
    TrainTicket getTicket(String trainNumber, String date);
}

// TrainTicketDaoImpl类，实现了TrainTicketDao接口
public class TrainTicketDaoImpl implements TrainTicketDao {
    private List<TrainTicket> ticketList = new ArrayList<>();

    @Override
    public void addTicket(TrainTicket ticket) {
        ticketList.add(ticket);
    }

    @Override
    public void deleteTicket(String trainNumber, String date) {
        Iterator<TrainTicket> iter = ticketList.iterator();
        while (iter.hasNext()) {
            TrainTicket ticket = iter.next();
            if (ticket.getTrainNumber().equals(trainNumber) && ticket.getDate().equals(date)) {
                iter.remove();
                break;
            }
        }
    }

    @Override
    public void updateTicket(TrainTicket ticket) {
        for (int i = 0; i < ticketList.size(); i++) {
            TrainTicket t = ticketList.get(i);
            if (t.getTrainNumber().equals(ticket.getTrainNumber()) && t.getDate().equals(ticket.getDate())) {
                ticketList.set(i, ticket);
                break;
            }
        }
    }

    @Override
    public TrainTicket getTicket(String trainNumber, String date) {
        for (TrainTicket ticket : ticketList) {
            if (ticket.getTrainNumber().equals(trainNumber) && ticket.getDate().equals(date)) {
                return ticket;
            }
        }
        return null;
    }
}

// 测试代码
public class Test {
    public static void main(String[] args) {
        TrainTicketDao ticketDao = new TrainTicketDaoImpl();

        // 添加火车票
        ticketDao.addTicket(new TrainTicket("G1234", "北京", "上海", "2021-01-01"));
        ticketDao.addTicket(new TrainTicket("G5678", "上海", "北京", "2021-01-02"));

        // 查询火车票
        TrainTicket ticket1 = ticketDao.getTicket("G1234", "2021-01-01");
        System.out.println(ticket1);

        // 修改火车票
        ticket1.setDestination("广州");
        ticketDao.updateTicket(ticket1);
        TrainTicket ticket2 = ticketDao.getTicket("G1234", "2021-01-01");
        System.out.println(ticket2);

        // 删除火车票
        ticketDao.deleteTicket("G5678", "2021-01-02");
        TrainTicket ticket3 = ticketDao.getTicket("G5678", "2021-01-02");
        System.out.println(ticket3);
    }
}

这里定义了一个TrainTicket类表示火车票，包含车次、出发地、目的地和日期四个属性，以及getter和setter方法和toString方法。定义了一个TrainTicketDao接口，包含添加、删除、修改和查询火车票的方法。实现了TrainTicketDao接口的TrainTicketDaoImpl类，使用List存储火车票信息，并实现了添加、删除、修改和查询火车票的方法。最后，编写了一个测试类Test，用于测试火车订票系统的功能。