银行账户转帐方法

Question

好的，我在创建将“钱”从一个帐户转移到另一个帐户的方法时遇到问题。转账后，每个账户的金额将被打印出来。我创建了代码，但是当我运行它时，转账金额设置为银行账户金额。它应该只是从一个帐户中扣除并添加到下一个帐户。我做错了什么？

这是我的类与构造函数和方法：

public class Account {
// Instance variables
private double balance;

// Constructors
public Account(double initialBalance) {
    balance = initialBalance;
}

public Account(int account, double balance) {
    this.balance = balance;
}

public Account() {
    balance = 0.0;
}

// Instance methods

public void setBalance() {
    balance = Math.random() * 1000;
    balance = Math.round((balance * 100.0)+.5) / 100.0;
}

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

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

public double getBalance() {
    balance = Math.round((balance * 100.0)+.5) / 100.0;
    return balance;
}

public void close() {
    balance = 0.0;
}

public void transferTo(Account bank, double x) {
    if (x <= balance) {
        withdraw(x);
        bank.deposit(x);
        System.out.println("\nTransfer succesful. Tansfered: $" + bank.getBalance());
    } else if (x > balance) {
        System.out.println("\nTransfer failed, not enough balance!");
    }
}
}

这是我的主要方法的类

public class MyBank {

public static void main(String[] args) {

    Account[] bank = { new Account(), new Account(), new Account(),
            new Account() };

    bank[0].setBalance();
    bank[1].setBalance();
    bank[2].setBalance();
    bank[3].setBalance();

    System.out.println("Accounts 1 balance is: $" + bank[0].getBalance());
    System.out.println("Accounts 2 balance is: $" + bank[1].getBalance());
    System.out.println("Accounts 3 balance is: $" + bank[2].getBalance());
    System.out.println("Accounts 4 balance is: $" + bank[3].getBalance());

    double x = Math.random()*100;
    bank[0].transferTo(bank[1], x);
    System.out.println("Remaining balance of Account 1: $" + bank[0].getBalance());
    System.out.println("Remaining balance of Account 2: $" + bank[1].getBalance());

    double y = (Math.random()*300);
    bank[2].transferTo(bank[3], y);
    System.out.println("Remaining balance of Account 3: $" + bank[2].getBalance());
    System.out.println("Remaining balance of Account 4: $" + bank[3].getBalance());
}
}

Answer 1

您确实遇到的一个问题是，您在 transferTo() 方法中不小心打印了 BALANCE 而不是实际转移的金额。我解决了这个问题。另一方面，如果您要打印这些数字，look into printf() 使它们显示为实际的美元金额。为了给你看一个例子，我做了其中的一行。

PS - 尝试调试时尽量不要使用 Math.random()。

public void transferTo(Account bank, double x) {
    if (x <= this.balance) {
        withdraw(x);
        bank.deposit(x);
        System.out.println("\nTransfer succesful. Tansfered: $" + x);
    } else { //does not need to be else if, because if not <=, it MUST be >.
        System.out.println("\nTransfer failed, not enough balance!");
    }
}

在这些编辑之后，我可以验证该方法在我的机器上运行良好。这是我用来测试的：

public class MyBank {

public static void main(String[] args) {

    Account[] bank = { new Account(), new Account(), new Account(),
            new Account() };

    bank[0].setBalance();
    bank[1].setBalance();
    bank[2].setBalance();
    bank[3].setBalance();

    double x = 100.00;
    System.out.printf("Transferring $%.2f from Acc 1 to Acc 2.\n", x); //printf example
    System.out.println("Acc 1 previous balance: " + bank[0].getBalance());
    System.out.println("Acc 2 previous balance: " + bank[1].getBalance());
    bank[0].transferTo(bank[1], x);
    
    
    System.out.println("Acc 1 new balance: " + bank[0].getBalance());
    System.out.println("Acc 2 new balance: " + bank[1].getBalance());
        
        
}
}

最后，我的输出：

将 100.00 美元从 Acc 1 转移到 Acc 2。

Acc 1 之前的余额：106.76

Acc 2 之前的余额：266.18

传输成功。已转帐：$100.0

Acc 1 新余额：6.77

Acc 2 新余额：366.19

Answer 2

System.out.println("\nTransfer succesful. Tansfered: $" + bank.getBalance());

这会打印另一个帐户的新余额，因为这是你告诉它的。

如果您想打印转账金额：

System.out.println("\nTransfer succesful. Tansfered: $" + x);

Answer 3

// Bank account class
class BankAccount {
  constructor(fname, lname, account_number) {
    const minBalance = 10000;
    this.name = `${fname} ${lname}`;
    this.balance = minBalance;
    this.account_number = account_number;
  }

  details() {
    console.log(
      `Cleint name: ${this.name} \n Balance: ${this.balance} \n Account number: ${this.account_number}`
    );
  }

  isPositive(amount) {
    return amount > 0 ? true : false;
  }

  isVlaidAmount(amount) {
    return isNaN(amount) || !this.isPositive(amount) ? false : true;
  }

  deposit(amount) {
    if (this.isVlaidAmount(amount)) {
      this.balance += amount;
    } else {
      console.log("Sorry, this transcation cannot be completed!");
    }
  }

  withdraw(amount) {
    if (this.isVlaidAmount(amount)) {
      this.balance -= amount;
    } else {
      console.log("Sorry, you have insufficient funds.");
    }
  }

  transfer(amount, reciever) {
    if (this.isVlaidAmount(amount)) {
      this.withdraw(amount);
      reciever.deposit(amount);
    }
  }
}

// create objects
let acc1 = new BankAccount("George", "Omara", 422);
let acc2 = new BankAccount("Haward", "Walowets", 662);