[JAVA][Beginning Java 8 Games Development]

Chapter 10 ■ Directing the Cast of Actors: Creating a Casting Director Engine and Creating the Bagel Actor Class
Figure 10-15. The Hero abstract class has a public boolean collide() method but since it is not abstract it is not required
You might be wondering why we didn’t make .collide() into an abstract method, which it’s important to note that
we could do, at any point in time in the future. The reason is that we might want to have (add in) motion sprites that
do not collide with anything in the scene (game play) at some point in your future game development, perhaps to add
in visual detail elements, such as a bird flying across the top of the screen. The choice is yours to make, so if you want
motion sprites to always collide with things, you could declare the .collide() method to be abstract as well.
The important thing to note is that we can still override the .collide() method, which I am going to do next,
just to show you that this can still be done without the method having to be declared using the Java abstract keyword
and the Bagel class will use the overridden .collide() method rather than the “default” method in the Hero superclass,
which returns a false value (no collision).
What is important to make a note of here is that you can put your default method code into the superclass,
which, if not specifically overridden in any given subclass, will become your default method programming logic for all
of your subclasses. This allows you to implement “default” behaviors for all your subclasses, in one place (superclass).
Of course, you can always override this default behavior, and implement a more specific behavior, using the
@Override keyword along with the same exact method declaration format. This can be seen in Figure 10-16, near the
bottom of the screen shot, and if you compare this with the bottom of Figure 10-15, you will see that their structure is
identical, with the exception of the @Override keyword used in the Bagel subclass. When we cover collision detection
programming, we’ll replace the return false; line of code with our Bagel class’s own customized .collide() collision
detection behavior, which will become quite complex as we add advanced features to the game as time goes on. For
now I am installing this .collide() method body (essentially empty, as it just returns false) so you see a complete class.
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