银行ATM机模拟系统（Java+jdbc+mysql数据库）

概述：

最近做了一个简易的银行ATM机模拟系统，能够利用jdbc操作数据库，模拟了一些简单的功能，如下面所示：

1.查询余额
2.存钱
3.取钱
4.转账
5.查询交易记录
6.注销账户
7.修改密码
8.退出系统

有需要jdbc驱动jar包和mysql数据库文件的伙伴可以留言或私信我。

详细代码：

import java.sql.*;
import java.text.SimpleDateFormat;
import java.util.Scanner;
import java.util.Date;

public class bankAtm{
    static final String JDBC_DRIVER = "com.mysql.cj.jdbc.Driver";
    static final String DB_URL = "jdbc:mysql://localhost:3306/bank_manage?serverTimezone=UTC&useSSL=false";
    static final String USER = "root"; 
    static final String PASS = "1234"; //数据库密码
    public static void show(String name) throws ClassNotFoundException, SQLException {
        Connection conn = null;
        PreparedStatement stmt = null;
        Class.forName(JDBC_DRIVER);
        conn = DriverManager.getConnection(DB_URL, USER, PASS);
        String sql1 = "SELECT * FROM account_tab where name = ?";
        stmt = conn.prepareStatement(sql1);
        stmt.setString(1,name);
        ResultSet rs = stmt.executeQuery();
        double amount = 0;
        while(rs.next()) {
            amount = rs.getDouble("account");
        }
        System.out.println("账户余额为："+amount);
        rs.close();
        stmt.close();
        conn.close();
    }
    public static void deposit(String name) throws ClassNotFoundException, SQLException {
        Connection conn = null;
        PreparedStatement stmt = null;
        Class.forName(JDBC_DRIVER);
        conn = DriverManager.getConnection(DB_URL, USER, PASS);
        String sql1 = "SELECT * FROM account_tab where name = ?";
        stmt = conn.prepareStatement(sql1);
        stmt.setString(1,name);
        ResultSet rs = stmt.executeQuery();
        double oldAmount = 0;
        while(rs.next()) {
            oldAmount = rs.getDouble("account");
        }
        System.out.println("请输入存入的金额:");
        Scanner sc = new Scanner(System.in);
        double amount = sc.nextDouble();
        double newAmount = amount + oldAmount;
        String sql2 = "update account_tab set account =? where name =?";
        stmt = conn.prepareStatement(sql2);
        stmt.setDouble(1,newAmount);
        stmt.setString(2,name);
        int res = stmt.executeUpdate();
        if(res!=0){
            System.out.println("操作成功，余额为:"+newAmount);
            record(name,"存入",amount);
        }
        else{
            System.out.println("操作失败!");
        }
        rs.close();
        stmt.close();
        conn.close();
    }
    public static void withdraw(String name) throws ClassNotFoundException, SQLException {
        Connection conn = null;
        PreparedStatement stmt = null;
        Class.forName(JDBC_DRIVER);
        conn = DriverManager.getConnection(DB_URL, USER, PASS);
        String sql1 = "SELECT * FROM account_tab where name = ?";
        stmt = conn.prepareStatement(sql1);
        stmt.setString(1,name);
        ResultSet rs = stmt.executeQuery();
        double oldAmount = 0;
        while(rs.next()) {
            oldAmount = rs.getDouble("account");
        }
        System.out.println("请输入取出的金额:");
        Scanner sc = new Scanner(System.in);
        double amount = sc.nextDouble();
        double newAmount = oldAmount - amount;
        if(newAmount<0){
            System.out.println("取出金额大于账户余额!");
        }
        else {
            String sql2 = "update account_tab set account =? where name =?";
            stmt = conn.prepareStatement(sql2);
            stmt.setDouble(1, newAmount);
            stmt.setString(2, name);
            int res = stmt.executeUpdate();
            if (res != 0) {
                System.out.println("操作成功，余额为:" + newAmount);
                record(name,"取出",amount);
            } else {
                System.out.println("操作失败!");
            }
        }
        rs.close();
        stmt.close();
        conn.close();
    }
    public static void transfer(String name) throws ClassNotFoundException, SQLException {
        Connection conn = null;
        PreparedStatement stmt = null;
        Class.forName(JDBC_DRIVER);
        conn = DriverManager.getConnection(DB_URL, USER, PASS);
        String sql1 = "SELECT * FROM account_tab where name = ?";
        stmt = conn.prepareStatement(sql1);
        stmt.setString(1,name);
        ResultSet rs = stmt.executeQuery();
        double oldAmount = 0;
        while(rs.next()) {
            oldAmount = rs.getDouble("account");
        }
        System.out.println("请输入要转入的账户:");
        Scanner sc = new Scanner(System.in);
        String sql2 = "SELECT * FROM account_tab where name = ?";
        stmt = conn.prepareStatement(sql2);
        String targetAccount = sc.next();
        stmt.setString(1,targetAccount);
        ResultSet rs1 = stmt.executeQuery();
        double targetAmount = 0;
        if(rs1.next()){
            targetAmount = rs1.getDouble("account");
            System.out.println("请输入转出金额:");
            double amount = sc.nextDouble();
            double newAmount = oldAmount - amount;
            if(newAmount<0){
                System.out.println("转出金额大于账户余额!");
            }
            else {
                targetAmount = targetAmount + amount;
                String sql3 = "update account_tab set account =? where name =?";
                stmt = conn.prepareStatement(sql3);
                stmt.setDouble(1, newAmount);
                stmt.setString(2, name);
                int res1 = stmt.executeUpdate();
                String sql4 = "update account_tab set account =? where name =?";
                stmt = conn.prepareStatement(sql4);
                stmt.setDouble(1, targetAmount);
                stmt.setString(2, targetAccount);
                int res2 = stmt.executeUpdate();
                if ((res1!=0)&&(res2!=0)) {
                    System.out.println("操作成功，余额为:" + newAmount);
                    record(name,"转出",amount);
                    record(targetAccount,"转入",amount);
                } else {
                    System.out.println("操作失败!");
                }
            }
        }
        else{
            System.out.println("不存在该账户!");
        }
        rs.close();
        stmt.close();
        conn.close();
    }
    public static boolean accountDisposal(String name) throws ClassNotFoundException, SQLException {
        System.out.println("您正在执行注销户操作,请确认是否继续:");
        System.out.println("1.继续");
        System.out.println("2.返回");
        Scanner sc = new Scanner(System.in);
        int choice = sc.nextInt();
        if(choice==1) {
            Connection conn = null;
            PreparedStatement stmt = null;
            ResultSet rs = null;
            // 注册 JDBC 驱动
            Class.forName(JDBC_DRIVER);
            // 打开链接
            conn = DriverManager.getConnection(DB_URL, USER, PASS);
            // 执行查询
            String sql = "delete from account_tab where name=?";
            stmt = conn.prepareStatement(sql);
            stmt.setString(1, name);
            int result = stmt.executeUpdate();
            if(result!=0){
                System.out.println("注销账户成功!");
                System.out.println("已自动退出系统!!");
                return true;
            }
            else{
                System.out.println("操作失败!");
            }
        }
        else{
            System.out.println("操作取消!");
            return false;
        }
        return false;
    }
    public static void changePassword(String name) throws ClassNotFoundException, SQLException {
        System.out.println("请输入旧密码:");
        Scanner sc = new Scanner(System.in);
        String oldPassword = sc.next();
        String newPassword =null;
        String sql = "select * from account_tab where name=? and password = ?; ";
        Connection conn = null;
        PreparedStatement stmt = null;
        // 注册 JDBC 驱动
        Class.forName(JDBC_DRIVER);
        // 打开链接
        conn = DriverManager.getConnection(DB_URL, USER, PASS);
        // 执行查询
        stmt = conn.prepareStatement(sql);
        PreparedStatement ps = conn.prepareStatement(sql);
        ps.setString(1, name);
        ps.setString(2, oldPassword);
        ResultSet rs = ps.executeQuery();
        if (rs.next()) {
            System.out.println("请输入新密码:");
            newPassword = sc.next();
            if(newPassword.length()!=6){
                System.out.println("新密码不符合要求!!!");
                System.out.println("必须为六位数字!!!");
            }
            else{
                String sql1 = "update account_tab set password =? where name =?";
                stmt = conn.prepareStatement(sql1);
                stmt.setString(1, newPassword);
                stmt.setString(2, name);
                int res2 = stmt.executeUpdate();
                if(res2!=0){
                    System.out.println("密码修改成功!!!");
                }
                else{
                    System.out.println("操作失败!!!");
                }
            }
        }
        else{
            System.out.println("密码错误!!!");
            System.out.println("操作已终止!!!");
        }
    }
    public static void showRecord(String name) throws ClassNotFoundException, SQLException {
        Connection conn = null;
        PreparedStatement stmt = null;
        Class.forName(JDBC_DRIVER);
        conn = DriverManager.getConnection(DB_URL, USER, PASS);
        String sql = "SELECT * FROM record_tab where name =?";
        stmt = conn.prepareStatement(sql);
        stmt.setString(1,name);
        ResultSet rs = stmt.executeQuery();
        while (rs.next()) {
// 通过字段检索

            String type = rs.getString("type");
            double amount = rs.getDouble("amount");
            Timestamp time = rs.getTimestamp("time");
// 输出数据
            System.out.print("交易类型: "+type+"\t");
            System.out.print("交易金额: "+amount+ "\t");
            System.out.print("交易时间: "+time+"\t");
            System.out.print("\n");
        }
// 完成后关闭
        rs.close();
        stmt.close();
        conn.close();
    }
    public static void record(String name,String type,double amount) throws ClassNotFoundException, SQLException {
        Connection conn = null;
        PreparedStatement stmt = null;
        ResultSet rs = null;
        // 注册 JDBC 驱动
        Class.forName(JDBC_DRIVER);
        // 打开链接
        conn = DriverManager.getConnection(DB_URL, USER, PASS);
        Date date = new Date();//获得当前时间
        Timestamp t = new Timestamp(date.getTime());//将时间转换成Timestamp类型，这样便可以存入到Mysql数据库中
        String sql = "insert into record_tab(name,type,amount,time) values(?,?,?,?)";
        stmt = conn.prepareStatement(sql);
        stmt.setString(1,name);
        stmt.setString(2,type);
        stmt.setDouble(3,amount);
        stmt.setTimestamp(4,t);
        stmt.executeUpdate();
    }
    public static boolean login(String name) throws ClassNotFoundException, SQLException {
        System.out.println("请输入密码:");
        Scanner sc = new Scanner(System.in);
        String password = sc.next();
        String sql = "select * from account_tab where name=? and password = ?; ";
        Connection conn = null;
        PreparedStatement stmt = null;
        // 注册 JDBC 驱动
        Class.forName(JDBC_DRIVER);
        // 打开链接
        conn = DriverManager.getConnection(DB_URL, USER, PASS);
        // 执行查询
        stmt = conn.prepareStatement(sql);
        PreparedStatement ps = conn.prepareStatement(sql);
        ps.setString(1, name);
        ps.setString(2, password);
        ResultSet rs = ps.executeQuery();
        if (rs.next()) {
            System.out.println("成功进入系统!");
            System.out.print("进入时间:");
            SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");//设置日期格式
            System.out.println(df.format(new Date()));// new Date()为获取当前系统时间
            rs.close();
            stmt.close();
            conn.close();
            return true;
        } else {
            System.out.println("账号或密码错误!");
            rs.close();
            stmt.close();
            conn.close();
            return false;
        }
    }
    public static boolean doMain(String name) throws SQLException, ClassNotFoundException {
        System.out.println("请选择功能：");
        System.out.print("1.查询余额");
        System.out.print("\t2.存钱");
        System.out.print("\t3.取钱");
        System.out.print("\t4.转账");
        System.out.print("\t5.查询交易记录");
        System.out.print("\t6.注销账户");
        System.out.print("\t7.修改密码");
        System.out.println("\t8.退出系统");
        Scanner sc1 = new Scanner(System.in);
        int choice = sc1.nextInt();
        switch (choice) {
            case 1:
                show(name);
                break;
            case 2:
                deposit(name);
                break;
            case 3:
                withdraw(name);
                break;
            case 4:
                transfer(name);
                break;
            case 5:
                showRecord(name);
                break;
            case 6:
                boolean flag = accountDisposal(name);
                if(flag == true)
                    return false;
                break;
            case 7:
                changePassword(name);
                break;
            case 8:
                System.out.println("退出成功");
                return false;
        }
        return true;
    }
    public static void main(String args[]) throws SQLException, ClassNotFoundException {
        boolean flag = true;
        boolean userFlag = false;
        String name=null;
        System.out.println("欢迎使用模拟ATM系统!!!");
        System.out.println("请选择:");
        System.out.println("1.进入系统");
        System.out.println("2.退出");
        Scanner sc = new Scanner(System.in);
        int choice = sc.nextInt();
        if(choice==1){
            System.out.println("请输入账户:");
            Scanner sc1 = new Scanner(System.in);
            name = sc1.next();
            userFlag=login(name);
        }
        else{
            System.out.println("退出成功!");
        }
        while(flag&&userFlag){
            flag=doMain(name);
        }
    }
}