数据库要求：
创建数据库、表
创建数据库 account
- 创建一张表 t_ccount。有以下列
- cardId： 字符串，主键
- password： 字符串，非空
- username： 字符串，非空
- balance： 小数，非空
- phone： 字符串，非空
功能实现要求：
创建项目通过JDBC实现功能
创建AccountSystem类，完成下列功能
- 开户： 控制台输入所有的账户信息，使用PreparedStatement添加至t_account表
- 存款： 输入卡号、密码、存储金额进行修改
- 取款： 输入卡号、密码、取款金额
- 转账： 输入卡号、密码、对方卡号、转账金额进行修改
- 修改密码： 输入卡号、密码，再输入新密码进行修改
- 查看余额： 输入卡号、密码，查询余额
- 注销： 输入卡号、密码，删除对应的账户信息
数据库操作
#创建数据库
create database account character set utf8;
#使用account数据库
use account;
#创建表
create table t_account
(
card_id character(20) primary key,
password character(50) not null,
username character(20) not null,
balance double(10, 2) not null,
phone character(11) not null
) character set utf8;
功能实现
import java.util.Scanner;
/**
* 菜单
*/
public class TestAccount {
public static void main(String[] args) {
AccountSystem accountSystem = new AccountSystem();
Scanner scanner = new Scanner(System.in);
System.out.println("欢迎使用中国银行ATM机");
int choice = 0;
do {
System.out.println("1.开户 2.存款 3.取款 4.转账 5.修改密码 6.查看账户余额 7.注销 0.退出");
System.out.print("请选择你的操作：");
choice = scanner.nextInt();
switch (choice) {
case 1:
accountSystem.register();
break;
case 2:
accountSystem.saveMoney();
break;
case 3:
accountSystem.takeMoney();
case 4:
accountSystem.transfers();
break;
case 5:
accountSystem.updatePassword();
break;
case 6:
accountSystem.getBalance();
break;
case 7:
accountSystem.logout();
break;
case 0:
accountSystem.closeConnection();
return;
default:
break;
}
} while (choice != 0);
}
}
import java.sql.*;
import java.util.Scanner;
/**
* 要求：
* <p>
* 开户：输入所有的账户信息，使用PreparedStatement添加至t_account表中
* 存款：输入卡号、密码、存储金额进行修改
* 取款：输入卡号、密码、取款金额
* 转账：输入卡号、密码、需要对其转账的卡号、转账金额进行修改
* 修改密码：输入卡号、密码，再输入新密码进行修改
* 查询余额：输入卡号、密码，查询出对应的卡内余额
* 注销：输入卡号、密码，删除对应的账户信息
*/
public class AccountSystem {
Scanner scanner = new Scanner(System.in);
private static Connection connection = null;
PreparedStatement preparedStatement = null;
ResultSet resultSet = null;
static {
//重复的操作，就出发一次加载即可！
try {
//1.加载驱动
Class.forName("com.mysql.jdbc.Driver");
//2.连接数据库
connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/account?useUnicode=true&characterEncoding=utf8", "root", "123456");
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
}
}
/**
* 关闭数据库连接对象Connection
* <p>
* 注意：在程序结束时关闭，如果过早关闭的话，将与数据库断开连接
* 所以我们放在退出ATM机系统时调用关闭
*/
public void closeConnection() {
if (connection != null) {
try {
connection.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
//开户
public void register() {
System.out.print("请输入卡号：");
String card_id = scanner.next();
System.out.print("请输入密码：");
String password = scanner.next();
System.out.print("请输入用户名：");
String username = scanner.next();
System.out.print("请输入存储金额：");
double balance = scanner.nextDouble();
System.out.print("请输入预留手机号：");
String phone = scanner.next();
//3.创建PreparedStatement，预编译
String sql = "insert into t_account(card_id, password, username, balance, phone) values (?, ?, ?, ?, ?)";
try {
preparedStatement = connection.prepareStatement(sql);
//4.为占位符赋值
preparedStatement.setString(1, card_id);
preparedStatement.setString(2, password);
preparedStatement.setString(3, username);
preparedStatement.setDouble(4, balance);
preparedStatement.setString(5, phone);
//5.执行SQL语句
int result = preparedStatement.executeUpdate();
//6.处理结果
if (result > 0) {
System.out.println("开户成功！");
} else {
System.out.println("开户失败！");
}
} catch (SQLException e) {
e.printStackTrace();
} finally {
if (preparedStatement != null) {
try {
preparedStatement.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
}
//存款
public void saveMoney() {
System.out.print("请输入卡号：");
String card_id = scanner.next();
System.out.print("请输入密码：");
String password = scanner.next();
System.out.print("请输入存储金额：");
double money = scanner.nextDouble();
if (money > 0) {
String sql = "update t_account set balance = balance + ? where card_id = ? and password = ?";
//预编译
try {
preparedStatement = connection.prepareStatement(sql);
//为占位符赋值
preparedStatement.setDouble(1, money);
preparedStatement.setString(2, card_id);
preparedStatement.setString(3, password);
//执行SQL语句
int result = preparedStatement.executeUpdate();
//处理结果
if (result > 0) {
System.out.println("存款成功！");
} else {
System.out.println("卡号或密码错误！");
}
} catch (SQLException e) {
e.printStackTrace();
} finally {
if (preparedStatement != null) {
try {
preparedStatement.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
} else {
System.out.println("输入存储金额错误！");
}
}
//取款
public void takeMoney() {
System.out.print("请输入卡号：");
String card_id = scanner.next();
System.out.print("请输入密码：");
String password = scanner.next();
System.out.print("请输入取出金额：");
double money = scanner.nextDouble();
if (money > 0) {
String sql = "update t_account set balance = balance - ? where card_id = ? and password = ?";
//预编译
try {
preparedStatement = connection.prepareStatement(sql);
//为占位符赋值
preparedStatement.setDouble(1, money);
preparedStatement.setString(2, card_id);
preparedStatement.setString(3, password);
//执行SQL语句
int result = preparedStatement.executeUpdate();
//处理结果
if (result > 0) {
System.out.println("取款成功！");
} else {
System.out.println("卡号或密码错误！");
}
} catch (SQLException e) {
e.printStackTrace();
} finally {
try {
preparedStatement.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
}
//查看余额
public void getBalance() {
System.out.print("请输入卡号：");
String card_id = scanner.next();
System.out.print("请输入密码：");
String password = scanner.next();
String sql = "select balance from t_account where card_id = ? and password = ?";
try {
preparedStatement = connection.prepareStatement(sql);
preparedStatement.setString(1, card_id);
preparedStatement.setString(2, password);
ResultSet resultSet = preparedStatement.executeQuery();
if (resultSet.next()) {
double balance = resultSet.getDouble("balance");
System.out.println("卡内余额为：" + balance);
} else {
System.out.println("卡号或密码错误！");
}
} catch (SQLException e) {
e.printStackTrace();
} finally {
if (resultSet != null) {
try {
resultSet.close();
} catch (SQLException e) {
e.printStackTrace();
}
} else if (preparedStatement != null) {
try {
preparedStatement.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
}
//修改密码
public void updatePassword() {
System.out.print("请输入卡号：");
String card_id = scanner.next();
System.out.print("请输入密码：");
String password = scanner.next();
System.out.print("请输入新密码：");
String newPassword = scanner.next();
String sql = "update t_account set password = ? where card_id = ? and password = ?";
try {
preparedStatement = connection.prepareStatement(sql);
preparedStatement.setString(1, newPassword);
preparedStatement.setString(2, card_id);
preparedStatement.setString(3, password);
int result = preparedStatement.executeUpdate();
if (result > 0) {
System.out.println("密码修改成功！");
} else {
System.out.println("卡号或密码错误！请核对后再修改！");
}
} catch (SQLException e) {
e.printStackTrace();
} finally {
if (preparedStatement != null) {
try {
preparedStatement.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
}
//注销
public void logout() {
System.out.print("请输入卡号：");
String card_id = scanner.next();
System.out.print("请输入密码：");
String password = scanner.next();
String sql = "delete from t_account where card_id = ? and password = ?";
try {
preparedStatement = connection.prepareStatement(sql);
preparedStatement.setString(1, card_id);
preparedStatement.setString(2, password);
int result = preparedStatement.executeUpdate();
if (result > 0) {
System.out.println("注销成功！");
} else {
System.out.println("卡号或密码错误！");
}
} catch (SQLException e) {
e.printStackTrace();
} finally {
if (preparedStatement != null) {
try {
preparedStatement.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
}
//转账
public void transfers() {
System.out.print("请输入付款卡号：");
String card_id = scanner.next();
System.out.print("请输入付款密码：");
String password = scanner.next();
System.out.print("请输入转账金额：");
double money = scanner.nextDouble();
if (money > 0) {
String sql1 = "select balance from t_account where card_id = ? and password = ?";
try {
preparedStatement = connection.prepareStatement(sql1);
preparedStatement.setString(1, card_id);
preparedStatement.setString(2, password);
ResultSet resultSet = preparedStatement.executeQuery();
if (resultSet.next()) {
double balance = resultSet.getDouble("balance");
if (money <= balance) {
System.out.print("请输入收款卡号：");
String toCard_id = scanner.next();
String sql2 = "select balance from t_account where card_id = ?";
preparedStatement = connection.prepareStatement(sql2);
preparedStatement.setString(1, toCard_id);
resultSet = preparedStatement.executeQuery();
if (resultSet.next()) {
String sql3 = "update t_account set balance = balance - ? where card_id = ?";
preparedStatement = connection.prepareStatement(sql3);
preparedStatement.setDouble(1, money);
preparedStatement.setString(2, card_id);
preparedStatement.executeUpdate();
String sql4 = "update t_account set balance = balance + ? where card_id = ?";
preparedStatement = connection.prepareStatement(sql4);
preparedStatement.setDouble(1, money);
preparedStatement.setString(2, toCard_id);
preparedStatement.executeUpdate();
System.out.println("转账成功！");
} else {
System.out.println("收款卡号不存在！");
}
} else {
System.out.println("卡内余额不足！");
}
} else {
System.out.println("卡号或密码错误！");
}
} catch (SQLException e) {
e.printStackTrace();
} finally {
try {
if (resultSet != null) {
resultSet.close();
}
if (preparedStatement != null) {
preparedStatement.close();
}
} catch (SQLException e) {
e.printStackTrace();
}
}
} else {
System.out.println("请重新验证，输入正确的转账金额！");
this.transfers();
}
}
