How to override a method in a subclass and call the parent class method without losing data

Question

This is only the second time I use this, and the first time I got really good help so I am hoping I could get some more help!

Background:

My program tests my Account class by creating an object that holds a balance and other things. The instructions say I need to override the subclasse's "Withdraw" and "Deposit" methods in order to keep track of a transaction.

I did this, but it doesn't use the current balance and instead just sends in a 0. I want to be able to keep the new balance so it actually withdraws or deposits from the current balance.

Sorry if this makes no sense, if any clarification is needed I will try to explain in a different way.

Below is my code snippet:

Note: I kept out the stuff that already works (constructors and other methods) that has nothing to do with this:

Account.java

public class Account
{    
    private static double balance;

    public void Withdraw(double withdrawAmount)
    {
        this.balance -= withdrawAmount;
    }
    public void Deposit(double depositAmount)
    {
        this.balance += depositAmount;
    }
}

UserAccount.java

public class UserAccount extends Account
{
    private ArrayList<Transactions> transactions = new ArrayList();
    @Override
    public void Withdraw(double withdrawAmount)
    {
        super.Withdraw(withdrawAmount);
        Transactions thisTransaction = new Transactions('W', 
        withdrawAmount, this.AccBalance(), "Withdraw");
        this.transactions.add(thisTransaction);
    }
    @Override
    public void Deposit(double depositAmount)
    {
        super.Deposit(depositAmount);
        Transactions thisTransaction = new Transactions('D', 
        depositAmount, this.AccBalance(), "Deposit");
        this.transactions.add(thisTransaction);
    }
    public void fillTransactions(char type, double amount, double balance)
    {
        switch (type) {
            case 'D':
                this.Deposit(amount);
                break;
            case 'W':
                this.Withdraw(amount);
                break;
            default:
                System.out.println("ERROR fillTransactions");
                break;
        }
    }
    public static void main(String[] args) {
        ArrayList<Transactions> copyTransactions;
        UserAccount thisAccount = new UserAccount("George", 1122, 1000);
        thisAccount.MutAIR(.015);

        thisAccount.fillTransactions('D', 30, thisAccount.AccBalance());
        thisAccount.fillTransactions('D', 40, thisAccount.AccBalance());
        thisAccount.fillTransactions('D', 50, thisAccount.AccBalance());
        thisAccount.fillTransactions('W', 5, thisAccount.AccBalance());
        thisAccount.fillTransactions('W', 4, thisAccount.AccBalance());
        thisAccount.fillTransactions('W', 2, thisAccount.AccBalance());
}

The Transactions class that I have holds the type (withdraw or deposit), the amount getting withdrawn or deposited, and the balance. What happening is when I call the super class from the overridden deposit or withdraw methods, it sets balance to 0 so it says that the balance is 50, or 40, or -5 when I want the original balance with the deposited or withdrawn currency.

If anyone could help, that would be amazing! I can clarify if anything is confusing! Thank you!

Answer 1

Hey I think you are not setting the balance in the constructor of UserAccount.
Here's an example of setting variable Assume class A as Account and class B as UserAccount

class A {
  private double balance;// Don't use static
  public A(double balance) {// You will need this
      this.balance = balance;
  }
  public double getBalance() { return balance; }
}
class B extends A {
  public B(double balance) { 
      super(balance);//Important
  }
  public void d() { System.out.println(getBalance()); }
}
public class Main {
  public static void main(String args[]) {
    B b = new B(100.0);
    b.d();
  }
}

If you use static balance in the super class, then only one instance of it will be used for all the objects, since you want individual balance for each UserAccount I guess.