Question

我正在尝试学习没有任何编程经验的Java，所以我正在学习一个教程，但是我被困在一个我无法理解的部分。在本教程中，我制作了一个模拟BankAccount函数并尝试对其进行测试。但是，我陷入了＆＃34; setOverdraftAccount＆＃34;功能。

这是我的测试代码：

    /**
Class TestBank
**/
//MAKE NO CHANGES TO THIS CLASS OTHER THAN UNCOMMENTING LINES ONE BY ONE
//MODIFY THE BankAccount CLASS TO CORRECT ERRORS REVEALED AS YOU UNCOMMENT THE LINES 
public class TestBank {
    private static int counter = 0;

    public static void main(String [] args) {
        BankAccount b1 = new BankAccount(254.36);
        printBalance(b1, 254.36);//must produce "b1 balance = 254.36..."
//         
        double amt = 100.00;
//         
        b1.deposit(amt);
        printBalance(b1, 354.36);//must produce "b1 balance = 354.36..."
//         
        b1.withdraw(100.00);
        printBalance(b1, 254.36);
//        
        BankAccount b2 = new BankAccount(123.45);//must produce "b2 balance = 123.45..."
        printBalance(b2, 123.45);
//         
        b2.deposit(amt*2);
        printBalance(b2, 323.45);
//         
        b2.withdraw(10.56);
        printBalance(b2, 312.89);
//         
        b1.transfer(154.36, b2); //transfer $154.36 from account b1 to account b2
            printBalance(b1, 100.00);
            printBalance(b2, 467.25);
//          
            BankAccount b3 = new BankAccount(83.80);
            printBalance(b3, 83.80); //must produce "b3 balance = 83.80..."
//         
            b1.setOverdraftAccount(b2); // set b2 as the overdraft account for b1
//         //if account balance goes below zero, funds are transferred from overdraft account in $50 increments to cover shortfall
//         
            b2.setOverdraftAccount(b3); //set b3 as the overdraft account for b2
//         
            b1.withdraw(554.50);
            printBalance(b1, 45.50);
            printBalance(b2, 17.25);
            printBalance(b3, 33.80);


    private static void printBalance(BankAccount b, double expectedBalance) 
        {
            counter++;
            System.out.println(counter + ". " +  b.getAccountNumber()+ " balance = "+ b.getBalance() + " --> must be "+ expectedBalance);
        }
}

public class BankAccount {
    private double balance;
    private String accountNumber;
    private static int counter = 1;
    private BankAccount overdraftAccount = null;

    public BankAccount(double balance) {
        this.balance = balance;
        this.accountNumber = "b"+counter;
        counter++;


    }
    public String getAccountNumber() {
        return accountNumber;

    }
    public double getBalance() {
        return balance;
    }

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

    public void transfer(double amount, BankAccount other) {
        this.withdraw(amount);
        other.deposit(amount);
    }

    public void setOverdraftAccount(BankAccount b) {
        overdraftAccount = b;
    }
}

在我的Testbank课程中，它说＆＃34; b1.setOverdraftAccount（b2）＆＃34;它描述了当资金低于0时程序应该做什么，在这种情况下增加50美元。有人能指出我应该做些什么来解决这个问题，而不向TestBank类添加任何内容吗？

我有一种感觉，我应该在我的＆＃34; setOverdraftAccount＆＃34;中添加一个while循环。功能是为了从我的透支帐户中提取50，但我不知道如何将50添加到b1的余额中。

使用透支方法，用于测试银行帐户功能

0 个答案: