java/W3/BankAccount.java

class BankAccount {
    private final String accountNumber;
    private String ownerName;
    private double balance;

    public BankAccount(String accountNumber, String ownerName) {
        this.accountNumber = accountNumber;
        this.ownerName = ownerName;
        this.balance = 0.0;
    }

    public void deposit(double amount) {
        if (amount > 0) {
            this.balance += amount;
            System.out.println("[业务] 存入 $" + amount + " 成功。");
        } else {
            System.out.println("[业务] 存款失败：金额必须大于0。");
        }
    }

    public void withdraw(double amount) {
        if (amount > 0 && amount <= this.balance) {
            this.balance -= amount;
            System.out.println("[业务] 取出 $" + amount + " 成功。");
        } else {
            System.out.println("[业务] 取款失败：余额不足或金额无效。");
        }
    }

    public double getBalance() {
        return this.balance;
    }

    public String getOwnerName() {
        return this.ownerName;
    }
}