java/w3/BankAccount.java

public 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 String getAccountNumber(){
        return accountNumber;
    }

    public String getOwnerName(){
        return ownerName;
    }

    public void setOwnerName(String ownerName) {
        if (ownerName == null || ownerName.isBlank()) {
            throw new IllegalArgumentException("invalid ownerName");
        }
        this.ownerName = ownerName.strip();
    }

    public double getBalance(){
        return balance;
    }

    public void deposit(double amount){
        if (amount > 0){
            balance += amount;
            System.out.println("存款成功，当前余额为"+balance+"元");
        } else {
            System.out.println("存款金额必须大于0");
        }
    }

    public void withdraw(double amount){
        if (amount>0 && amount<=balance){
            balance -= amount;
            System.out.println("取款成功，当前余额为"+balance+"元");
        } else if (amount<=0){
            System.out.println("取款金额必须大于0");
        } else {
            System.out.println("取款金额不能超过当前余额");
        }
    }
}