Question

Beginning object oriented programming in Java:


public class BankAccount{
private double myBalance;

public BankAccount(double initialBalance){
myBalance = initialBalance;
}
public void deposit(double amount){
double newBalance = myBalance + amount;
myBalance = newBalance;
}
public double getBalance(){
return myBalance;
}
}

Answer 1

//in another class


public class driver
{
public static void main(String [] args){
BankAccount b1 = new BankAccount(500);
BankAccount b2 = new BankAccount(200);
b1.deposit(b2.getBalance());
b2.deposit(b1.getBalance());

}
}

Answer 2

What are the balances of b1 and b2 after the code is executed?

Answer 3

The code that confuses me is b1.deposit(b2.getBalance());
First, the value of b2 goes into the method getBalance, which returns 200. Now it is b1.deposit(200); but what does that do? I don't understand and the debugger isn't much help.

Answer 4

Please explain. How does that happen?

Answer 5

Like, in the first time you run b1.deposit(b2.getBalance()); why does amount = 200 and mybalance = 500?? It says that in my debugger. I don't understand that one bit.

Answer 6

Shouldn't amount = 500 and mybalance = 200?

Answer 7

Inside the main(), the 1st line says B1 = 500
the 2nd line says B2 = 200.
The third line says that you're depositing the amount of money in B2 into B1, therefore 500+200 = 700 dollars.
The fourth line says that you're now depositing the amount of money from B1 into B2, so 200 + 700 = 900 dollars.

Therefore, B1 has 700 dollars and B2 has 900 dollars.

Answer 8

MAH sleek-feathered oneH! Okay, I think I understand it way better now. :)
Thank you again!