[Java知识库]Java练习（三十三）---继承练习&存款取款，每次存取款扣一元手续费

public class BankTest {
    public static void main(String[] args) {
       CheckingAccount c = new CheckingAccount(300);
        c.deposit(100);
        c.withdraw(20);
    }
}

class Bank {
    private double balance;//余额

    public void Bank(double balance) {
        this.balance = balance;
    }

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

    //取款
    public void withdraw(double amount) {
        while (balance < amount) {
            System.out.println("余额不足，请重新输入金额");
            break;
        }
        if (balance > amount) {
            balance -= amount;
        }
     
    }

    public double getBalance() {
        return balance;
    }

    public void setBalance(double balance) {
        this.balance = balance;
    }
}

class CheckingAccount extends Bank {
  public CheckingAccount(double balance) {
        super(balance);
    }

    @Override
    public void deposit(double amount) {
         super.deposit(amount - 1);
    }
    @Override
    public void withdraw(double amount) {
        super.withdraw(amount + 1);
    }
     //这里需要注意是先计算amount+1,然后再用balance-amount
}

输出结果：
399.0
378.0