Question

I am trying to construct a method that will allow me to find the total cost of a number of items in an arraylist. Currently I have an arraylist full of “items.” In the item class the objects have a price and a quantity found by getQuantity and getPrice. I’m trying to find the total cost of all the items in the arraylist but keep getting 5 errors. Can anyone help thanks,

EDIT: Posted the errors

 public double getTotalCost()
         {

            double total;
            for(int i = 0; i < cart.size; i++) // size has private access in ArrayList
            {
                total = ((cart.get(i)).getQuantity) * ((cart.get(i)).getPrice) + total; // cannot find symbol // illegal start of type// cannot find symbol // illegal start of type
            }


            return total;
         }   
    }

Answer 1

To call a method on a object, you always need to use parentheses. So not cart.size but cart.size(). If you do not, Java expects you are requesting a public variable for a object. size is a private variable in your List Object and therfore gives you a private access error

public double getTotalCost(){
  double total = 0;
  for(int i = 0; i < cart.size(); i++){
    total =  ( cart.get(i).getQuantity() * cart.get(i).getPrice() ) + total;
  }
  return total;
}