Core Java Programming (JCP)

This was my first serious subject at ITAcademy and also my introduction to Java. I learned the basics of object-oriented programming:

• Classes and objects
• Inheritance and polymorphism
• Abstract classes and interfaces
• Collections (List, Set, Map)

Code Example

class Animal {
    void sound() { System.out.println("Some sound..."); }
}
class Dog extends Animal {
    @Override void sound() { System.out.println("Woof!"); }
}
public class Main {
    public static void main(String[] args) {
        Animal dog = new Dog();
        dog.sound(); // Woof!
    }
}