java银行账户管理系统简单源代码

在Java中设计一个简单的银行账户管理系统，我们可以创建一个基本的体系结构，主要包括`Account`, `SavingsAccount`, 和 `CheckingAccount` 类。这里我将给出一个简化的示例：

// 定义一个抽象的Account类作为基础
public abstract class Account {
    private String accountNumber;
    private double balance;

    public Account(String accountNumber) {
        this.accountNumber = accountNumber;
        this.balance = 0;
    }

    // 公共方法
    public void deposit(double amount) {
        if (amount > 0) {
            balance += amount;
        }
    }

    public void withdraw(double amount) {
        if (balance >= amount) {
            balance -= amount;
        } else {
            System.out.println("Insufficient funds.");
        }
    }

    public double getBalance() {
        return balance;
    }

    // 抽象方法，需要在子类中实现
    public abstract double calculateInterest();
}

// 子类SavingsAccount和CheckingAccount分别实现不同的利率计算
public class SavingsAccount extends Account {
    public SavingsAccount(String accountNumber) {
        super(accountNumber);
    }

    @Override
    public double calculateInterest() {
        return balance * 0.03; // 假设年利率为3%
    }
}

public class CheckingAccount extends Account {
    public CheckingAccount(String accountNumber) {
        super(accountNumber);
    }

    @Override
    public double calculateInterest() {
        if (balance < 500) {
            return 0;
        } else {
            return balance * 0.01; // 假设年利率为1% for balance above $500
        }
    }
}

// 主程序入口
public class BankAccountManager {
    public static void main(String[] args) {
        Account myAccount = new SavingsAccount("123456789");
        myAccount.deposit(1000);
        System.out.println("Initial balance: " + myAccount.getBalance());
        myAccount.withdraw(200);
        System.out.println("After withdrawal: " + myAccount.getBalance());

        // 调用子类方法
        double savingsInterest = ((SavingsAccount) myAccount).calculateInterest();
        System.out.println("Savings interest: " + savingsInterest);

        CheckingAccount checkingAccount = new CheckingAccount("987654321");
        System.out.println("Checking account interest: " + checkingAccount.calculateInterest());
    }
}