JAVA项目--银行管理系统

1、项目描述

银行管理系统：实现登录、注册，登录后的用户可以进行存款、取款、转账、查询余额操作

2、分析

创建银行类Bank：用于存储银行卡信息，并创建银行系统的主窗体
创建银行卡类BankCard：初始化银行卡信息
创建用户操作类User：进行存款、取款、转账、查询余额操作
创建测试类Main

3、代码
银行类Bank

import java.util.HashMap;
import java.util.Scanner;

//银行
public class Bank {
    //使用哈希列表存储银行的银行卡号信息
    public static HashMap<Integer, BankCard> bankCards = new HashMap<>();

    //注册账户方法
    public void register(int cardNo, int password) {
        //判断该卡号是否存在
        if (bankCards.containsKey(cardNo)) {
            System.out.println("该账户已经存在，麻烦重新选择业务");
            return;
        }
        BankCard bankCard = new BankCard(cardNo,password);
        bankCards.put(cardNo, bankCard);
        System.out.println("注册成功！");
    }

    //登录
    public BankCard login(int cardNo, int password) {
        if (bankCards.size() == 0) {
            System.out.println("当前不存在任何银行卡信息，建议及时注册！");
            return null;
        }
        //判断该账户是否存在
        if (bankCards.containsKey(cardNo)){
            if (bankCards.get(cardNo).getPassword() == password) {
                //如果密码正确，则登录成功
                return bankCards.get(cardNo);
            } else {
                System.out.println("登录失败，该密码错误！");
                //否则就返回null
                return null;
            }
        }else {
            System.out.println("登录失败，该账户不存在!");
        }
        return null;
    }

    //进入银行界面
    public void manager(User user) {
        //输入密码次数不能超过5次,如果输入错误次数超过5次，则退出系统
        int number = 5;
        while (number > 0) {
            System.out.println("***欢迎来到本银行，请选择您的业务：***");
            System.out.println("1.登录账户");
            System.out.println("2.注册账户");
            System.out.println("3.退出");
            System.out.println("请输入您的选择：");
            Scanner scanner = new Scanner(System.in);
            int key = scanner.nextInt();
            int cardNo;
            int password;
            switch (key) {
                case 1:
                    System.out.println("请输入您的银行卡账号：");
                    cardNo = scanner.nextInt();
                    System.out.println("请输入您的银行卡密码：");
                    password = scanner.nextInt();
                    BankCard card = login(cardNo, password);
                    if (card != null) {
                        System.out.printf("***卡号：%d登陆成功***", cardNo);
                        while (true) {
                            System.out.println("");
                            System.out.println("***请输入您需要的业务***");
                            System.out.println("1.存钱");
                            System.out.println("2.取钱");
                            System.out.println("3.转账");
                            System.out.println("4.查询余额");
                            System.out.println("5.退卡");
                            int num = scanner.nextInt();
                            if (num == 5) break;
                            operate(user, num, card);
                        }
                    } else {
                        number--;
                        System.out.println("登陆失败！您还有"+number+"次机会");
                    }
                    break;
                case 2:
                    System.out.println("请输入您的银行卡账号：");
                    cardNo = scanner.nextInt();
                    System.out.println("请输入您的银行卡密码：");
                    password = scanner.nextInt();
                    register(cardNo, password);
                    break;
                case 3:
                    System.out.println("尊敬的用户，您已成功退出银行系统！欢迎下次光临~");
                    return;
                default:
                    System.out.println("请重新输入正确选项！");
            }

        }
    }

    private void operate(User user, int num, BankCard card) {
        switch (num) {
            case 1:
                user.deposit(card);
                break;
            case 2:
                user.withdraw(card);
                break;
            case 3:
                user.transfer(card);
                break;
            case 4:
                user.select(card);
                break;
            default:
                break;
        }
    }

}

银行卡类BankCard

//银行卡
public class BankCard {
    private int cardNo;//卡号
    private int password;//密码
    private double money;//余额

    //初始化
    public BankCard(int cardNo, int password) {
        this.cardNo = cardNo;
        this.password = password;
        //默认该账户初始值为100
        this.money = 100;
    }


    public void setPassword(int password) {
        this.password = password;
    }

    public void setMoney(double money) {

        this.money = money;
    }

    public int getPassword() {
        return password;
    }

    public double getMoney() {
        return money;
    }

    public int getCardNo() {
        return cardNo;
    }

    public void setCardNo(int cardNo) {
        this.cardNo = cardNo;
    }
}

用户操作类User

import java.text.DecimalFormat;
import java.util.Map;
import java.util.Scanner;

//操作
public class User {
    Scanner scanner = new Scanner(System.in);

    //存款
    public void deposit(BankCard bankCard) {
        System.out.println("请输入您的存入金额：");
        double money = scanner.nextDouble();
        if (money > 0) {
            bankCard.setMoney(bankCard.getMoney() + money);
            System.out.println("存款成功，本次存款金额为："+money);
            select(bankCard);
        } else {
            System.out.println("请输入正确金额");
        }
    }

    //取钱
    public void withdraw(BankCard bankCard) {
        System.out.println("请输入您要取出的金额：");
        double money = scanner.nextDouble();
        //取款金额大于0.且大于余额
        if (money > 0 && money <= bankCard.getMoney()) {
            //修改账户金额
            bankCard.setMoney(bankCard.getMoney() - money);
            System.out.println("取款成功，本次取款金额为："+money);
            select(bankCard);
        } else if (money > bankCard.getMoney()) {
            System.out.println("很抱歉，您的余额不足！");
        } else {
            System.out.println("请输入正确取款金额！");
        }
    }

    //查询余额
    public void select(BankCard card) {
        DecimalFormat df = new DecimalFormat("#.00");
        System.out.println("您的余额为： " + df.format(card.getMoney()));
    }

    //转账
    public void transfer(BankCard bankCard) {
        //限制输出账号的次数为3次
        int number = 3;
        while (number > 0) {
            System.out.println("请输入对方的卡号：");
            int destID = scanner.nextInt();//目的账号
            Map<Integer, BankCard> bankCards = Bank.bankCards;
            if (bankCards.containsKey(destID)) {
                //查找目的账户存在，再进行转账操作
                BankCard transferAccounts = bankCards.get(destID);
                System.out.println("请输入您要转账的金额：");
                double money = scanner.nextDouble();
                if (money <= bankCard.getMoney()) {
                    //修改账户余额
                    bankCard.setMoney(bankCard.getMoney() - money);
                    //修改对方账户余额
                    transferAccounts.setMoney(transferAccounts.getMoney() + money);
                    System.out.println("转账成功，本次转账金额为："+money);
                    select(bankCard);
                    return;
                } else {
                    System.out.println("很抱歉，您的余额不足！");
                }
            }
            System.out.println("您还有" + (number - 1) + "次机会，请重新输入转账账户");
            number--;
        }
    }


}

测试类Main

public class Main {
    public static void main(String[] args) {
        Bank bank = new Bank();
        User user = new User();
        //打开银行的系统界面
        bank.manager(user);
    }
}

4、效果