Java继承类有没有大神帮帮我

public class SavingsAccount {
    private int balance;

    public SavingsAccount(int balance) {
        this.balance = balance;
    }

    public void deposit(int amount) {
        if (amount > 0 && (amount % 10 == 0 || amount % 5 == 0)) {
            balance += amount;
            System.out.println("成功存入" + amount + "元，当前余额为" + balance + "元");
        } else {
            System.out.println("存入金额必须为正整数且为10或5的倍数");
        }
    }

    public int withdraw(int amount) {
        if (amount % 2 != 0) {
            System.out.println("取款金额必须为2的倍数");
            return 0;
        } else if (amount > balance) {
            System.out.println("余额不足");
            return 0;
        } else {
            balance -= amount;
            System.out.println("成功取出" + amount + "元，当前余额为" + balance + "元");
            return amount;
        }
    }

    public int getBalance() {
        return balance;
    }
}

public class SavingsAccountTest {
    public static void main(String[] args) {
        SavingsAccount account = new SavingsAccount(1000);
        account.deposit(50);
        account.deposit(15);
        account.deposit(-10);
        account.deposit(7);
        account.deposit(12);
        account.withdraw(5);
        account.withdraw(7);
        account.withdraw(100);
        account.withdraw(20);
        account.withdraw(30);
        System.out.println("当前余额为：" + account.getBalance());
    }
}