To expand on the answer by bradtgmurray, you may want to make one exception to the pure virtual method list of your interface by adding a virtual destructor. This allows you to pass pointer ownership to another party without exposing the concrete derived class. The destructor doesn’t have to do anything, because the interface doesn’t … Read more
Interface vs Abstract Class (general OO)
It is a standard way of how OOP works. Imagine a class Human. It is of course abstract as there can not be a concrete instance of a human. A concrete implementation could for example be a class Person that requires a name and some other information. public class Person extends Human { String name; … Read more
abstract class PhoneCall { String phoneNumber; double price; PhoneCall(String phoneNumber) { this.phoneNumber = phoneNumber; this.price = 0.0; } public String getPhoneNumber() { return phoneNumber; } public double getPrice() { return price; } public abstract void setPrice(); } class IncomingPhoneCall extends PhoneCall { final static double RATE=0.02; IncomingPhoneCall(String phoneNumber){ super(phoneNumber); setPrice(); } public void setPrice() { … Read more