使用java语言写代码模拟atm机

在Java中，我们可以创建一个简单的ATM模拟程序来展示多态的概念。首先，我们定义一个`BankAccount`接口，然后创建两个实现了这个接口的具体类，比如`SavingsAccount`和`CheckingAccount`。接着，我们可以定义一个`ATM`类，它有一个方法列表，其中包含对银行账户通用操作（如存款、取款和查询余额）。每个具体的账户类都提供它们特定的操作。

// 银行账户接口
interface BankAccount {
    void deposit(double amount);
    double withdraw(double amount) throws InsufficientFundsException;
    double getBalance();
}

// 存款账户类
class SavingsAccount implements BankAccount {
    private double balance;

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

    @Override
    public double withdraw(double amount) throws InsufficientFundsException {
        if (amount <= balance) {
            balance -= amount;
            return amount;
        } else {
            throw new InsufficientFundsException("Insufficient funds");
        }
    }

    @Override
    public double getBalance() {
        return balance;
    }
}

// 普通检查账户类
class CheckingAccount extends SavingsAccount {
    // 检查账户可能有不同的费用处理逻辑
    @Override
    public double withdraw(double amount) throws InsufficientFundsException {
        double withdrawal = super.withdraw(amount - 0.5); // 每次取款扣除0.5元手续费
        System.out.println("Transaction fee: $0.50");
        return withdrawal;
    }
}

// ATM类
class ATM {
    public void performOperation(BankAccount account, String operation, double amount) {
        switch (operation.toLowerCase()) {
            case "deposit":
                account.deposit(amount);
                break;
            case "withdraw":
                try {
                    double withdrawn = account.withdraw(amount);
                    System.out.printf("Withdrawal successful! Amount withdrawn: %.2f\n", withdrawn);
                } catch (InsufficientFundsException e) {
                    System.out.println(e.getMessage());
                }
                break;
            case "balance":
                System.out.printf("Current balance: %.2f\n", account.getBalance());
                break;
            default:
                System.out.println("Invalid operation.");
        }
    }
}

public class Main {
    public static void main(String[] args) {
        ATM atm = new ATM();
        atm.performOperation(new SavingsAccount(), "Deposit", 1000);
        atm.performOperation(new CheckingAccount(), "Withdraw", 800);
    }
}