java - Java完全错误银行帐户类

更新:通过添加到实例字段来修复错误。 - 谢谢。

第二个问题:我可以将“ Activity 帐户”设置为可变变量，并为实际帐户提供机会吗？如果是这样，怎么办？

编译程序时，我在MainMenu方法中遇到找不到符号“activeaccount”的问题。我对为什么会收到此错误感到困惑，因为我在构造函数中建立了“activeaccount”对象。有任何想法吗？先感谢您!

public class Account
{

  /**
  * Constructor for objects of class Account
  */
  public Account()
  {
    BankAccount activeaccount = new BankAccount("Seth Killian", "Savings", 500.00, 6.0, 0.25, 10000.00);
  }

  public void MainMenu()
  {
    Scanner in = new Scanner (System.in);
    switch (in.nextInt())
    {
      case 0:
       Initialize();

      case 1: //Check balance
       activeaccount.printBalance();
       SelectOption();

      case 2: //Make a deposit
       double amount;
       System.out.print("Deposit Amount: $");
       amount = in.nextDouble();
       activeaccount.deposit(amount);
       SelectOption();

      case 3: //Make a withdrawl
       System.out.print("Withdrawl Amount: $");
       amount = in.nextDouble();
       activeaccount.withdrawl(amount);
       SelectOption();

      case 4: //Apply Annual Interest
       activeaccount.addInterest();
       SelectOption();

      case 5: // Print Log
       activeaccount.printLog();
       SelectOption();

      case 6: // Exits application
       System.exit(0);

      default: // Unrecognized Selection
       System.out.println ("Error: Selection Unrecognized");
       SelectOption();
    }
  }

最佳答案

activeaccount仅存在于构造函数的scope中。如果要在该类的其他部分访问activeaccount，请为其创建一个instance variable:

private BankAccount activeaccount; // the instance variable

public Account() {
    activeaccount = new BankAccount("Seth Killian", "Savings", 500.00, 6.0, 0.25, 10000.00);
}

或一行(可以省略构造函数):

private BankAccount activeaccount = new BankAccount("Seth Killian", "Savings", 500.00, 6.0, 0.25, 10000.00);