I can't seem to find the reason why its "error: cannot find symbol"

Question

[免责声明：初学者 Java]

我的程序运行刚刚遇到问题，而我正试图完成它。错误是它找不到符号，IDE （我正在使用 Text Pad） 在 main 方法中精确定位它，检查下面：

BalanceW.java:22: error: cannot find symbol
        account.withdraw(500.00);
               ^
  symbol:   method withdraw(double)
  location: variable account of type Account

如果你想知道代码，给你：

Account.java

public class Account{
    private String accntNumber;
    private String accntName;
    private double balance;

    public Account(){}
    public Account(String num, String name, double bal){
        accntNumber = num;
        accntName = name;
        balance = bal;
    }

    public double getBalance(){ return balance;}
}

BalanceW.java (我把main方法压缩在了Balance W里面所以post不会太长)

public class BalanceW extends Account{

    public double withdraw(double amount){
        double bal = getBalance();
            if(amount <= 0){
                throw new ArithmeticException("Invalid amount: Amount is less than 0");
            }
            if(amount > bal){
                throw new ArithmeticException("Insufficient: Insufficient funds");
            }
            bal = bal - amount;
            return amount;

    }
        public static void main(String[] args){
        Account account = new Account("Acct-001","Juan dela Cruz", 5000.0);
        account.withdraw(500.00);
        System.out.println("Balance: "+account.getBalance());
    }
}

我只想知道怎么出错，为什么出错。公平地说，我查找了多个选项卡以寻找修复错误的方法。非常感谢您阅读 post，如果您能帮助我解决这个问题，我将不胜感激。

Answer 1

withdraw 方法是为 BalanceW 定义的，而不是为 Account 定义的。如果你要使用这个方法，在方法main的第一行你需要声明账户为BalanceW，如下所示：

BalanceW account = new BalanceW("Acct-001", "Juan dela Cruz", 5000.0);
account.withdraw(500.00);

I can't seem to find the reason why its "error: cannot find symbol"

I can't seem to find the reason why its "error: cannot find symbol"

java

methods

cannot-find-symbol