public class BankAccount {
     private 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) {
             balance += amount;
             System.out.println("存款成功！当前余额：" + getBalance());
         } else {
             System.out.println("存款失败：金额必须大于0！");
         }
     }
     public void withdraw(double amount) {
         if (amount <= 0) {
             System.out.println("取款失败：金额必须大于0！");
         } else if (amount > balance) {
             System.out.println("取款失败：余额不足！当前余额：" + getBalance());
         } else {
             balance -= amount;
             System.out.println("取款成功！当前余额：" + getBalance());
         }
     }
     public double getBalance() {
         return Math.round(balance * 100.0) / 100.0;
     }
     public String getAccountNumber() {
         return accountNumber;
     }
     public void setOwnerName(String ownerName) {
         this.ownerName = ownerName;
     }
     public String getOwnerName() {
         return ownerName;
     }
 }