Java实现快递寄件记录管理_文件持久化入门项目

public class Express {
    private String number;  // 快递单号
    private String sender;  // 寄件人
    private String receiver; // 收件人
    private String phone;   // 收件人电话
    private String address; // 收件地址
    private long timestamp; // 寄件时间

    // 构造方法
    public Express(String number, String sender, String receiver, 
                   String phone, String address) {
        this.number = number;
        this.sender = sender;
        this.receiver = receiver;
        this.phone = phone;
        this.address = address;
        this.timestamp = System.currentTimeMillis();
    }

    // Getter 和 toString 方法（略）
}

import java.io.*;
import java.util.*;

public class ExpressService {
    private List<Express> records = new ArrayList<>();
    private static final String FILE_PATH = "express.txt";

    // 加载数据
    public void loadFromFile() {
        records.clear();
        File file = new File(FILE_PATH);
        if (!file.exists()) return;

        try (BufferedReader br = new BufferedReader(new FileReader(file))) {
            String line;
            while ((line = br.readLine()) != null) {
                String[] parts = line.split(",");
                if (parts.length == 6) {
                    Express e = new Express(parts[0], parts[1], parts[2], parts[3], parts[4]);
                    records.add(e);
                }
            }
        } catch (IOException e) {
            System.out.println("读取文件失败：" + e.getMessage());
        }
    }

    // 保存数据
    public void saveToFile() {
        try (BufferedWriter bw = new BufferedWriter(new FileWriter(FILE_PATH))) {
            for (Express e : records) {
                bw.write(String.join(",", e.getNumber(), e.getSender(), e.getReceiver(),
                        e.getPhone(), e.getAddress()));
                bw.newLine();
            }
        } catch (IOException e) {
            System.out.println("保存文件失败：" + e.getMessage());
        }
    }

    // 添加记录
    public boolean addExpress(Express e) {
        if (findExpressByNumber(e.getNumber()) != null) {
            return false; // 单号重复
        }
        records.add(e);
        saveToFile();
        return true;
    }

    // 查询
    public Express findExpressByNumber(String number) {
        for (Express e : records) {
            if (e.getNumber().equals(number)) {
                return e;
            }
        }
        return null;
    }

    // 删除
    public boolean deleteExpress(String number) {
        Express target = findExpressByNumber(number);
        if (target != null) {
            records.remove(target);
            saveToFile();
            return true;
        }
        return false;
    }

    // 获取全部
    public List<Express> getAll() {
        return new ArrayList<>(records);
    }
}

import java.util.Scanner;

public class ExpressApp {
    private ExpressService service = new ExpressService();
    private Scanner scanner = new Scanner(System.in);

    public void start() {
        service.loadFromFile();
        System.out.println("=== 快递寄件管理系统 ===");

        while (true) {
            System.out.println("\n1. 添加记录");
            System.out.println("2. 查看所有记录");
            System.out.println("3. 查询单号");
            System.out.println("4. 删除记录");
            System.out.println("0. 退出");
            System.out.print("请选择：");

            int choice = scanner.nextInt();
            scanner.nextLine(); // 消费换行

            switch (choice) {
                case 1:
                    addRecord();
                    break;
                case 2:
                    showAll();
                    break;
                case 3:
                    query();
                    break;
                case 4:
                    delete();
                    break;
                case 0:
                    System.out.println("再见！");
                    return;
                default:
                    System.out.println("无效选择！");
            }
        }
    }

    private void addRecord() {
        System.out.print("单号："); String num = scanner.nextLine();
        System.out.print("寄件人："); String s = scanner.nextLine();
        System.out.print("收件人："); String r = scanner.nextLine();
        System.out.print("电话："); String p = scanner.nextLine();
        System.out.print("地址："); String a = scanner.nextLine();

        Express e = new Express(num, s, r, p, a);
        if (service.addExpress(e)) {
            System.out.println("添加成功！");
        } else {
            System.out.println("单号重复，添加失败！");
        }
    }

    private void showAll() {
        List<Express> list = service.getAll();
        if (list.isEmpty()) {
            System.out.println("暂无记录。");
        } else {
            for (Express e : list) {
                System.out.println(e);
            }
        }
    }

    private void query() {
        System.out.print("输入单号：");
        String num = scanner.nextLine();
        Express e = service.findExpressByNumber(num);
        if (e != null) {
            System.out.println("找到记录：" + e);
        } else {
            System.out.println("未找到该单号。");
        }
    }

    private void delete() {
        System.out.print("输入要删除的单号：");
        String num = scanner.nextLine();
        if (service.deleteExpress(num)) {
            System.out.println("删除成功！");
        } else {
            System.out.println("未找到该单号！");
        }
    }

    public static void main(String[] args) {
        new ExpressApp().start();
    }
}