Java Parking System Implementation Example

The article describes the design of a parking system where users can view available slots (up to 100), be assigned a random slot, pay based on parking duration (free for up to 3 hours, then 2 CNY per hour up to a maximum of 20 CNY), and check their parking history; administrators can view remaining slots, occupied slots, and payment records.

Below is the Java source code that implements the described functionality.

Client

package com.gem.client;
import java.util.Scanner;
import com.gem.entity.Admin;
import com.gem.entity.User;
import com.gem.service.impl.AdminServiceImpl;
import com.gem.service.impl.CarParkingServiceimpl;
import com.gem.service.impl.UserServiceimpl;

public class Client {
  public static void main(String[] args) {
    CarParkingServiceimpl carparkingservice = CarParkingServiceimpl.getCarparkingservice();
    UserServiceimpl userserviceimpl = UserServiceimpl.getUserserviceimpl();
    Scanner scanner = new Scanner(System.in);
    Menu1(carparkingservice, userserviceimpl, scanner);
  }

  private static void Menu1(CarParkingServiceimpl carparkingservice, UserServiceimpl userserviceimpl, Scanner scanner) {
    while (true) {
      System.out.println("****欢迎进入停车系统****");
      System.out.println("***1.请输入您的车牌***");
      System.out.println("***2.管理员***");
      System.out.println("***3.退出****");
      int choice = Integer.parseInt(scanner.nextLine().trim());
      switch (choice) {
        case 1:
          System.out.println("请输入您的车牌");
          String chepai = scanner.nextLine().trim();
          User a = userserviceimpl.login(new User(chepai));
          if (a != null) {
            System.out.println("车牌登记成功");
            Menu2(carparkingservice, userserviceimpl, scanner, a);
          } else {
            System.out.println("车牌登记失败");
          }
          break;
        case 2:
          Menu_Manger(carparkingservice, userserviceimpl);
          break;
        default:
          break;
      }
    }
  }

  //管理员的登录注册
  private static void Menu_Manger(CarParkingServiceimpl carparkingservice, UserServiceimpl userserviceimpl) {
    AdminServiceImpl adminserviceimpl = AdminServiceImpl.getAdminSeriver();
    while (true) {
      System.out.println("1.管理员登录");
      System.out.println("2.管理员注册");
      System.out.println("返回上一级");
      Scanner scanner = new Scanner(System.in);
      int chose = Integer.parseInt(scanner.nextLine().trim());
      switch (chose) {
        case 1:
          System.out.println("请输入管理员账号");
          String name = scanner.nextLine().trim();
          System.out.println("请输入管理员密码");
          String password = scanner.nextLine().trim();
          if (adminserviceimpl.login(name, password) != null) {
            System.out.println("登录成功");
            Menu_Manger2(carparkingservice, userserviceimpl, adminserviceimpl);
          } else {
            System.out.println("登录失败");
            return;
          }
          break;
        case 2:
          System.out.println("请输入注册账号");
          name = scanner.nextLine().trim();
          System.out.println("请输入注册密码");
          password = scanner.nextLine().trim();
          adminserviceimpl.register(new Admin(name, password));
          break;
        case 3:
          return;
        default:
          return;
      }
    }
  }

  //管理员操作
  private static void Menu_Manger2(CarParkingServiceimpl carparkingservice, UserServiceimpl userserviceimpl, AdminServiceImpl adminserviceimpl) {
    while (true) {
      System.out.println("***欢迎进入管理员操作***");
      System.out.println("1.查看现有停车位");
      System.out.println("2.查看停车位上的车以及缴费");
      System.out.println("3.返回上一级");
      Scanner scanner = new Scanner(System.in);
      int chose = Integer.parseInt(scanner.nextLine().trim());
      switch (chose) {
        case 1:
          carparkingservice.showlist();
          break;
        case 2:
          carparkingservice.show();
          break;
        case 3:
          return;
        default:
          System.out.println("输入错误");
          break;
      }
    }
  }

  private static void Menu2(CarParkingServiceimpl carparkingservice, UserServiceimpl userserviceimpl, Scanner scanner, User a) {
    while (true) {
      System.out.println("欢迎车牌为:" + a.getCarid() + "车主" + "请选择您要的服务");
      System.out.println("1.停车");
      System.out.println("2.离开并缴费");
      System.out.println("3.查看停车车位");
      System.out.println("4.停车时长");
      System.out.println("0.返回上一级");
      int chose = Integer.parseInt(scanner.nextLine().trim());
      switch (chose) {
        case 1:
          if (carparkingservice.chack(a.getCarid())) {
            break;
          }
          while (true) {
            int random = (int) (Math.random() * 10); //随机一个车位
            if (carparkingservice.parkcar(random, a.getCarid())) {
              System.out.println("停车成功,停车位置为:" + random);
              break;
            } else {
              System.out.println("当前车位有车");
            }
          }
          break;
        case 2:
          if (carparkingservice.leavecar(a.getCarid())) {
            System.out.println("请缴费");
          } else {
            System.out.println("该车未停");
          }
          break;
        case 3:
          carparkingservice.showlist();
          break;
        case 4:
          carparkingservice.showcartime(a.getCarid());
          break;
        case 0:
          return;
        default:
          System.out.println("输入错误");
          break;
      }
    }
  }
}

Admin Entity

package com.gem.entity;
import java.util.ArrayList;
import lombok.AllArgsConstructor;
import lombok.Getter;
import lombok.NoArgsConstructor;
import lombok.Setter;

@AllArgsConstructor
@NoArgsConstructor
@Getter
@Setter
public class Admin {
  private String username;
  private String password;
  private double money;
  private ArrayList
list = new ArrayList
();

  @Override
  public String toString() {
    return username + "\t" + password;
  }

  public Admin(String username, String password) {
    super();
    this.username = username;
    this.password = password;
  }
}

CarParking Entity

package com.gem.entity;
import java.text.SimpleDateFormat;
import java.util.Date;
import lombok.AllArgsConstructor;
import lombok.Getter;
import lombok.NoArgsConstructor;

@AllArgsConstructor
@NoArgsConstructor
@Getter
public class CarParking { //车位
  private static String lishi = "";
  private int id; //停车的编号
  private double money; //钱的计算
  private String state; //当前停车状态
  private Date stime; //停车时间
  private Date etime; //停车结束
  private static double allmoney;

  public static String getLishi() { return lishi; }
  public static void setLishi(String lishi) { CarParking.lishi = lishi; }

  public void setEtime() {
    etime = new Date();
    SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");
    String time = dateFormat.format(this.etime);
  }

  public void setStime() {
    stime = new Date();
    SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");
    String time1 = dateFormat.format(this.stime);
  }

  public String toString() {
    return id + "\t" + money + "\t" + stime;
  }

  public CarParking(int id, String state) {
    this.id = id;
    this.state = state;
  }

  public void CarPark(int id, String carid) {
    this.id = id;
    this.state = carid;
  }

  public int getId() { return id; }
  public void setId(int id) { this.id = id; }
  public double getMoney() { return money; }
  public void setMoney(double money) { this.money = money; }
  public String getState() { return state; }
  public void setState(String state) { this.state = state; }
  public static double getAllmoney() { return allmoney; }
  public static void setAllmoney(double allmoney) { CarParking.allmoney = allmoney; }
}

User Entity

package com.gem.entity;
import lombok.AllArgsConstructor;
import lombok.Getter;
import lombok.NoArgsConstructor;
import lombok.Setter;

@AllArgsConstructor
@NoArgsConstructor
@Getter
@Setter
public class User {
  private String carid; //车牌登录

  @Override
  public String toString() {
    return "车牌为" + carid;
  }
}

AdminService Interface

package com.gem.service;
import com.gem.entity.Admin;

public interface AdminService {
  //登录
  Admin login(String username, String password);
  //注册
  boolean register(Admin admin);
}

AdminServiceImpl

package com.gem.service.impl;
import java.util.ArrayList;
import com.gem.entity.Admin;
import com.gem.service.AdminService;

public class AdminServiceImpl implements AdminService {
  private ArrayList
adminList = new ArrayList
();
  //单例饿汉模式
  private static final AdminServiceImpl adminSeriver = new AdminServiceImpl();

  public static AdminServiceImpl getAdminSeriver() { return adminSeriver; }

  private AdminServiceImpl() {}

  @Override
  public Admin login(String username, String password) {
    for (Admin admin : adminList) {
      if (admin.getUsername().equals(username) && admin.getPassword().equals(password)) {
        return admin;
      }
    }
    return null;
  }

  @Override
  public boolean register(Admin admin) {
    return adminList.add(admin);
  }
}

CarParkingService Interface

package com.gem.service;
public interface CarParkingService {
  boolean parkcar(int id, String carid); //停车
  void showlist(); //显示所有列表
  boolean leavecar(String carid); //离开
}

CarParkingServiceimpl

package com.gem.service.impl;
import java.util.ArrayList;
import java.util.Date;
import com.gem.entity.CarParking;
import com.gem.service.CarParkingService;

public class CarParkingServiceimpl implements CarParkingService {
  private ArrayList
carpaking = new ArrayList
();
  {
    for (int i = 1; i <= 10; i++) {
      carpaking.add(new CarParking(i, "当前车位为空")); // 为10个车位赋予编号 和状态
    }
  }
  private static CarParkingServiceimpl carparkingservice = new CarParkingServiceimpl();
  public static CarParkingServiceimpl getCarparkingservice() { return carparkingservice; }
  public CarParkingServiceimpl() {}

  @Override
  public boolean parkcar(int id, String carid) {
    for (CarParking car : carpaking) {
      if (id == car.getId() && car.getState().equals("当前车位为空")) {
        car.setState(carid);
        car.setStime();
        return true; //停车成功
      }
    }
    return false; //当前车位有车
  }

  @Override
  public void showlist() {
    for (CarParking car : carpaking) {
      System.out.println(car.getId() + "\t" + car.getState());
    }
  }

  public void showcartime(String carid) {
    for (CarParking car : carpaking) {
      if (car.getState().equals(carid)) {
        car.setEtime();
        Date time1 = car.getEtime(); //当前时间
        Date time2 = car.getStime(); //开始时间
        System.out.println("车位为:" + car.getId() + "车牌为" + car.getState());
        System.out.println("停车时间为:" + car.getStime());
        System.out.println("当前时间为:" + car.getEtime());
        System.out.println("已经停车时间为:" + (time1.getTime() - time2.getTime()) / (1000 * 60 * 60));
      }
    }
  }

  @Override
  public boolean leavecar(String carid) {
    for (CarParking car : carpaking) {
      if (car.getState().equals(carid)) {
        car.setEtime();
        Date time1 = car.getEtime();
        Date time2 = car.getStime();
        long t = (time1.getTime() - time2.getTime()) / (1000 * 60 * 60);
        System.out.println("车位为:" + car.getId() + "车牌为" + car.getState());
        System.out.println("停车时间为:" + car.getStime());
        System.out.println("当前时间为:" + car.getEtime());
        System.out.println("已经停车时间为:" + t);
        if (t <= 3) {
          car.setMoney(0);
          CarParking.setAllmoney(CarParking.getAllmoney() + car.getMoney());
        } else if (t > 3 && t <= 13) {
          car.setMoney(2 * (t - 3));
          CarParking.setAllmoney(CarParking.getAllmoney() + car.getMoney());
        } else if (t > 13) {
          car.setMoney(20);
          CarParking.setAllmoney(CarParking.getAllmoney() + car.getMoney());
        }
        car.setLishi(car.getLishi() + "车位:" + car.getId() + "收入金额为:" + car.getMoney() + "\n");
        System.out.println("停车费为:" + car.getMoney());
        car.setState("当前车位为空");
        return true;
      }
    }
    return false;
  }

  public void show() {
    for (CarParking car : carpaking) {
      System.out.println(car.getLishi());
      return;
    }
  }

  public boolean chack(String carid) {
    for (CarParking car : carpaking) {
      if (car.getState().equals(carid)) {
        System.out.println("车辆正在停使中");
        return true;
      }
    }
    return false;
  }
}

UserService Interface

package com.gem.service;
import com.gem.entity.User;

public interface UserService {
  //用车牌登录
  User login(User a);
}

UserServiceimpl

package com.gem.service.impl;
import java.util.ArrayList;
import com.gem.entity.User;
import com.gem.service.UserService;

public class UserServiceimpl implements UserService {
  private ArrayList
user = new ArrayList
();
  private static UserServiceimpl userserviceimpl = new UserServiceimpl(); //单例

  private UserServiceimpl() {}

  public static UserServiceimpl getUserserviceimpl() { return userserviceimpl; }

  @Override
  public User login(User a) { //把车牌录入
    user.add(a);
    return a;
  }
}

The complete example demonstrates how to structure a simple parking management application using Java, covering entity modeling, service abstraction, singleton implementation, and console‑based user interaction.