Quick Tip: The OOP Principle of Abstraction

This entry is part 5 of 5 in the series Beginner's Guide to OOP
We’re almost done with this series on object-oriented programming, and in this article we’ll discuss the OOP principle of abstraction – that is, generalising an object – and its use in game development.
Note: Although this tutorial is written using Java, you should be able to use the same techniques and concepts in almost any game development environment.

---

What is Abstraction?

Abstraction is the principle of generalization. This requires that we move from a specific instance to a more generalized concept by thinking about the most basic information and function of an object.
This may sound a bit strange, but we are already familiar with the concept of abstraction. For example, if I say the word “car”, what do you think of? Odds are we weren’t thinking about the same car. I was thinking about a black Mustang Boss 302, which is a specific instance of a car. Neither of us were wrong because the word car is a very general concept of a vehicle that we use for transportation (or recreation in my case).
The same goes for video games. Video games are categorized into groups such as RTS, RPG, Racing, etc.. These groups are all generalized concepts that describe the gameplay of a game. StarCraft II, Elder Scrolls V: Skyrim, and Need for Speed are all specific instances of these generalized concepts.
Thus, abstraction takes many specific instances of objects and extracts their common information and functions to create a single generalized concept that can be used to describe all the specific instances as one.

---

Why is it Helpful?

Abstraction is helpful because it strips everything down to its most basic principles. This can help when encapsulating functionality of an object because it can help identify the important information that should be made visible and the unimportant information which can be made hidden.
Abstraction also helps with the Don’t Repeat Yourself principle. By taking what a group of objects have in common and abstracting it, we can help prevent redundant code in each object which in turn creates more maintainable code.

---

How to Apply This Principle

As before, let’s use our three games to see some concrete examples of this principle in action.

Asteroids

[...]
Read more: Quick Tip: The OOP Principle of Abstraction