In this chapter, we covered more theory than in any other chapter. If you haven't memorized everything or some of the code seemed a bit too in-depth, then you have still succeeded completely. If you just understand that OOP is about writing reusable, extendable, and efficient code through encapsulation, inheritance, and polymorphism, then you have the potential to be a Java master.
Simply put, OOP enables us to use other peoples' code even when those other people were not aware of exactly what we would be doing at the time they did the work. All you need to do is keep practicing. We will regularly be using what we have learned in this chapter throughout the book. This will reinforce what we have been talking about.
We also got started with the Pong project by creating an empty project along with all the classes that we will code over the next three chapters.
In the next chapter we will implement a basic game engine that can handle our game objects and in the process, we will learn...