Question

您好我在覆盖存款方法时遇到问题。我有一个BankAccount类（主要的），InterestAccount（扩展BankAccount）和IsaAccount（扩展InterestAccount）。我无法调用余额来添加IsaAccount类的存款方法中提到的金额。我尝试了很多方法使用getBalance，super（balance），super.getBalance等。没有任何作用。这让我筋疲力尽......我查看了许多类似的主题，但无法找到解决这一特定问题的方法。我必须存款方式才能将钱存入IsaAccount对象。

public class BankAccount {

     private int balance;

     public BankAccount() {
            balance = 0;
        }

    ......................


    public class InterestAccount extends BankAccount {

        private int interestRate;  
        private int minimumBalance; 


        public InterestAccount() {
            super();    
            interestRate = 0;
            minimumBalance = 100;
        }

    ......................

    public class IsaAccount extends InterestAccount {

        private int depositRemaining;

        public IsaAccount() {
            super();
            depositRemaining = 0;
        }

        public IsaAccount(int balance, int interestRate, int minimumBalance, int depositRemaining) {
            super(balance, interestRate, minimumBalance);
            this.depositRemaining = depositRemaining;

        }

        @Override
            public void deposit(int amount) {
            if (amount <= depositRemaining)
                 <HERE I NEED TO CALL BALANCE(not sure whether I have to use get 
                 methods or what) e.g balance = balance + amount; >
        }

    ......................

Answer 1

更新BankAccount以设置并获得

echo "$A"\_new

然后使用此方法（当然，因为您使用class BankAccount { private int balance; public BankAccount() { balance = 0; } public int getBalance() { return this.balance; } public void setBalance(int balance) { this.balance = balance; } }我假设它确实存在于父类中，如果没有则删除@Override

@Override

Answer 2

问题是您尝试从BankAccount访问的余额变量是私有的。当一个类扩展另一个类时，它会接收私有方法和变量，但它无法访问它们。您可以通过将余额更改为受保护而非私有来解决此问题。或者你可以在BankAccount中设置一个公共方法来设置余额。

@Override public void deposit(int amount) { if (amount <= depositRemaining){ setBalance(getBalance() + amount); } }而不是protected int balance;

或

private int balance;

无法访问＆＃34;来自超级，超级的变量

2 个答案: