如何实现Java控制台程序连接Mysql数据库模拟ATM操作？

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本文以Java模拟ATM功能为例，分享了整体的代码示例。主要包括三个类：Test.java、Customer.java、CustomerDAO.java和ATMSystem.java。

ATMSystem.java

javapublic class ATMSystem { public static void main(String[] args) { CustomerDAO customerDAO=new CustomerDAO(); Customer customer=customerDAO.getCustomer(123456);

if (customer !=null) { System.out.println(欢迎使用ATM系统); System.out.println(用户： + customer.getName()); System.out.println(余额： + customer.getBalance());

// 模拟ATM操作 customer.withdraw(100); // 提现100元 customer.deposit(200); // 存入200元

System.out.println(操作完成，当前余额： + customer.getBalance()); } else { System.out.println(用户不存在); } }}

Customer.java

javapublic class Customer { private String id; private String name; private double balance;

public Customer(String id, String name, double balance) { this.id=id; this.name=name; this.balance=balance; }

public String getId() { return id; }

public String getName() { return name; }

public double getBalance() { return balance; }

public void deposit(double amount) { balance +=amount; }

public void withdraw(double amount) { if (amount <=balance) { balance -=amount; } else { System.out.println(余额不足); } }}

CustomerDAO.java

javaimport java.util.HashMap;import java.util.Map;

public class CustomerDAO { private Map customers=new HashMap();

public CustomerDAO() { // 初始化用户数据 customers.put(123456, new Customer(123456, 张三, 1000.0)); customers.put(654321, new Customer(654321, 李四, 2000.0)); }

public Customer getCustomer(String id) { return customers.get(id); }}

Test.java

javapublic class Test { public static void main(String[] args) { ATMSystem.main(args); }}

以上代码演示了如何使用Java模拟ATM系统。主要包含用户信息管理、账户余额查询、存取款操作等功能。

本文实例为大家分享了java模拟ATM功能的具体代码，供大家参考，具体内容如下

有三个类：Test.java、Customer.java、CustomerDAO.java、ATMSystem.java

ATMSystem.java实现模拟ATM的功能

Customer.java创建一个用户对象

CustomerDAO.java实现连接数据库

Test为主程序

ATMSystem.java:

package ATM; import java.util.Scanner; public class ATMSystem { CustomerDAO dao=new CustomerDAO(); Scanner input=new Scanner(System.in); private int id; public ATMSystem() { } public void Regist() { System.out.println("注册卡号："); int myid=input.nextInt(); System.out.println("注册用户名："); String myname=input.next(); System.out.println("注册密码："); String mypwd=input.next(); System.out.println("输入存入金额："); int mymoney=input.nextInt(); dao.Regist(myid, mypwd, myname, mymoney); } public boolean login() { System.out.println("请输入密码："); String mypwd=input.next(); id=dao.login(mypwd); if(id==-1) { System.out.println("登录失败！"); return false; } else { System.out.println("登陆成功！"); return true; } } public void query(int id) { Customer cust=dao.query(id); System.out.println("********************"); System.out.println("卡号："+cust.getid()); System.out.println("余额："+cust.getmoney()); System.out.println("用户名："+cust.getname()); System.out.println("********************"); } public void save() { System.out.println("输入存款金额："); int money=input.nextInt(); dao.update_save(id, money); } public void get() { System.out.println("********************"); System.out.println("输入取款金额："); int money=input.nextInt(); dao.update_get(id, money); System.out.println("********************"); } public void change() { System.out.println("请输入转账卡号："); int inid=input.nextInt(); System.out.println("请输入转账金额："); int money=input.nextInt(); dao.change(id, inid, money); } public void begin() { int num=-1; int Num=0; System.out.println("请选择功能："); System.out.println("1.注册 2.登录"); Num=input.nextInt(); switch(Num) { case 1: Regist(); break; case 2: if(login()) { while(num!=0) { System.out.println("********************"); System.out.println("欢迎欢迎，热烈欢迎"); System.out.println("请选择功能："); System.out.println("1.存款 2.取款 3.查询 4.转账 0.退出"); System.out.println("********************"); num=input.nextInt(); switch(num) { case 1: save(); break; case 2: get(); break; case 3: query(id); break; case 4: change(); break; case 0: System.out.println("谢谢使用！"); break; } } } else { System.out.println("登录失败，账号、密码错误！"); } break; default: break; } } }

Customer.java

package ATM; public class Customer { private int id; private String pwd; private int money; private String name; public int getid() { return id; } public void setid(int newid) { id=newid; } public String getpwd() { return pwd; } public void setpwd(String newpwd) { pwd=newpwd; } public String getname() { return name; } public void setname(String newname) { name=newname; } public int getmoney() { return money; } public void setmoney(int newmoney) { money=newmoney; } }

CustomerDAO.java:

package ATM; import java.sql.Connection; import java.sql.DriverManager; import java.sql.ResultSet; import java.sql.SQLException; public class CustomerDAO { private Connection conn=null; private java.sql.PreparedStatement p=null; public CustomerDAO() { try { Class.forName("org.gjt.mm.mysql.Driver"); } catch (ClassNotFoundException e) { // TODO Auto-generated catch block e.printStackTrace(); } try { conn=DriverManager.getConnection("jdbc:mysql://localhost:3306/mysql", "root", ""); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } } public int login(String mypwd) { String sql="select * from mysql where pwd = ?"; try { p=conn.prepareStatement(sql); p.setString(1, mypwd); ResultSet rs=p.executeQuery(); if(rs.next()) { return rs.getInt("id"); } rs.close(); p.close(); conn.close(); } catch (SQLException e) { e.printStackTrace(); } return -1; } public Customer query(int id) { Customer cust=new Customer(); try { String sql="select * from mysql where id = ?"; p=conn.prepareStatement(sql); p.setInt(1, id); ResultSet rs=p.executeQuery(); if(rs.next()) { cust.setid(rs.getInt("id")); cust.setmoney(rs.getInt("money")); cust.setname(rs.getString("name")); cust.setpwd(rs.getString("pwd")); } } catch (Exception e) { // TODO: handle exception } return cust; } public void update_get(int id,int money) { String sql="select * from mysql where id = ?"; try { p=conn.prepareStatement(sql); p.setInt(1, id); ResultSet rs=p.executeQuery(); if(rs.next()) { if(rs.getInt("money")<money) { System.out.println("余额不足！"); } else { sql="update mysql set money = money - ? where id = ?"; p=conn.prepareStatement(sql); p.setInt(1, money); p.setInt(2, id); p.executeUpdate(); System.out.println("取款成功！"); } } } catch (Exception e) { // TODO: handle exception } } public void update_save(int id,int money) { String sql="update mysql set money = money + ? where id = ?"; try { p=conn.prepareStatement(sql); p.setInt(1, money); p.setInt(2, id); p.executeUpdate(); System.out.println("存款成功！"); } catch (Exception e) { // TODO: handle exception } } public void change(int myid,int inid,int money) { try { String sql="select * from mysql where id = ?"; p=conn.prepareStatement(sql); p.setInt(1, inid); ResultSet rs=p.executeQuery(); if(rs.next()) { sql="select * from mysql where id = ?"; p=conn.prepareStatement(sql); p.setInt(1, myid); rs=p.executeQuery(); if(rs.next()) { if(rs.getInt("money")<money) { System.out.println("余额不足！"); return; } else { sql="update mysql set money = money - ? where id = ?"; p=conn.prepareStatement(sql); p.setInt(1, money); p.setInt(2, myid); p.executeUpdate(); sql="update mysql set money = money + ? where id = ?"; p=conn.prepareStatement(sql); p.setInt(1, money); p.setInt(2, inid); p.executeUpdate(); } } } else { System.out.println("卡号错误！"); } } catch (Exception e) { // TODO: handle exception } } public void Regist(int myid,String mypwd,String myname,int mymoney) { String sql; try { sql="select * from mysql where id = ?"; p=conn.prepareStatement(sql); p.setInt(1, myid); ResultSet rs=p.executeQuery(); if(rs.next()) { System.out.println("此卡已注册，请勿重复注册！！！！"); return; } } catch (Exception e) { // TODO: handle exception } try { sql="insert into mysql(id,pwd,money,name) values(?,?,?,?)"; p=conn.prepareStatement(sql); p.setInt(1, myid); p.setString(2, mypwd); p.setInt(3, mymoney); p.setString(4, myname); p.executeUpdate(); System.out.println("注册成功！"); } catch (Exception e) { // TODO: handle exception } } }

Test.java:

package ATM; public class Test { public static void main(String[] args) { // TODO Auto-generated method stub ATMSystem ATM=new ATMSystem(); while(true) { ATM.begin(); } } }

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