[JAVA][Beginning Java 8 Games Development]

Chapter 10 ■ Directing the Cast of Actors: Creating a Casting Director Engine and Creating the Bagel Actor Class
Game Design: Adding Our CastingDirector.java class
The first thing that I want to do to is to update our invincibagel package and class structure diagram to show you
the new actor (sprite) management class that we are going to develop during this chapter using Java ArrayList and
HashSet classes (objects). As you can see in Figure 10-1, I am going to name this class CastingDirector.java because
it will act just like a Casting Director would for any entertainment project, adding Actors to the project, and removing
them when the scene is finished. This class will also contain a Java collection (a Java ListArray is an ordered collection
and a Java HashSet is an unordered collection) that will be used when we start to implement collision detection later
on during the book. As your game levels and scenes get more complicated, you will be glad to have a CastingDirector
class that keeps your game actors organized and adds and removes actors from the game as needed by your game’s
programming logic. It is important to keep track of exactly how many Actor (fixed sprites) and Hero (motion sprites)
objects are in the scene, so that you only involve the fewest possible number of actors in your collision detection code
(algorithms). This is a function of optimizing your game programming logic so the game plays well across all platforms.
Figure 10-1. Create a CastingDirector.java actor casting and tracking engine to keep track of Actor and Hero objects
Before we code our CastingDirector.java class, let’s take some time to learn about Java collections, generics, and
the List, ListArray, Set and HashSet classes that we are going to use to create these actor management tools.
List and ArrayList: Using java.util List Management
First, let’s cover the public class ArrayList because it is a class, and then we will look at List as that is an Interface,
and not a Java class. In case you are wondering what the stands for, it stands for Element, if you see a that
stands for Key, if you see a that stands for Type, and if you see a that stands for Value. The gets replaced
by an element (object) that you’re using in an ArrayList. In our case that is ArrayList as CastingDirector.java
class ArrayList (and Set) will reference Actor objects (subclasses of Actor superclass). The class hierarchy is as follows:
java.lang.Object
> java.util.AbstractCollection
> java.util.AbstractList
> java.util.ArrayList
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