Question

当我要求用户从余额中提取金额时，我遇到了问题。我有一个名为withdraw的方法，我通过他们的平衡。然后我想检查他们想要提取的金额是否小于他们的余额。如果是，我想让用户重试。

到目前为止，它会检查输入，但我会继续为每次尝试获取输出。

public void withdraw (double balance){
System.out.println("How much would you like to withdraw?");
double amount = keyboard.nextDouble();  

try
{
    if(amount > balance)
    {
        throw new IncorrectWithdrawException();
    }
}

catch(IncorrectWithdrawException e)
{
    System.out.println(e.getMessage());
    withdraw(balance);// keeps calling the method for a loop if they keep entering incorrect amount
}

balance = balance-amount;
System.out.println("You have withdrawn "+amount+ " and your new balance is "+balance); }}

输出：

你的余额是多少？ 100 你想退出多少钱？200 ------错误------这不是一个有效的退出金额。你要退多少钱？ 500 ------错误------这不是一个有效的退出金额。你要退多少钱？ 50

您已撤回50.0且新余额为50.0

我不希望下面的最后两个输出......

您已撤回500.0且您的新余额为-400.0您已撤回200.0并且您的新余额为-100.0

Answer 1

public void withdraw (double balance)
{
  System.out.println("How much would you like to withdraw?");
  double amount = keyboard.nextDouble();  

  try
  {
   if(amount < balance)
   {
    balance = balance-amount;
    System.out.println("You have withdrawn "+amount+ " and your new balance is "+balance);
   }
  else
   throw new IncorrectWithdrawException();
  }
 catch(IncorrectWithdrawException e)
 {
    System.out.println(e.getMessage());
    withdraw(balance);// keeps calling the method for a loop if they keep entering incorrect amount
 }
 }

提取异常Java

1 个答案: