[JAVA][Beginning Java 8 Games Development]

Chapter 3 ■ A Java 8 Primer: An Introduction to Java 8 Concepts and Principles
currentlyMoving (a new object will not be moving when it appears, even if that is only for a fraction of a second)
variables, which you will initialize, as you did for the default constructor. The other five variables (states) will be set using
parameters passed in via a parameter list, using an equals assignment operator. This is done using the following code:
GamePiece(int x, int y, String orientation, int lifespan, String direction, String movement) {
invinciBagelX = x;
invinciBagelY = y;
bagelOrientation = orientation;
lifeIndex = lifespan;
hitsIndex = 0;
directionFacing = direction;
movementType = movement;
currentlyMoving = false;
}
I bolded the variables in the parameter list, as well as where they are used inside the constructor method, to set the
states (variables) for the object. These variables are declared at the top of the GamePiece class, which you have used
to design, define, and create the GamePiece object. This second constructor method can be said to overload the first
constructor method, because it uses the exact same method call (method name), with a different parameter list (full of
parameters, versus empty or no parameters). This gives you the default object constructor method as well as a custom
object constructor method, so in your game logic, you can create a default GamePiece or a custom GamePiece.
Summary
In this third chapter you took a look at some of the more important concepts and structures found in the Java 8
programming language. Certainly, I cannot cover everything in Java in one chapter, so I stuck with concepts, constructs,
and keywords that you will be using to create a game over the course of this book. Most Java books are 800 pages or more,
so if you want to get really deep into Java, I suggest Beginning Java 8 Fundamentals by Kishori Sharan (Apress, 2014).
You started by taking a high-level view of Java, considering its syntax, including Java comments and delimiters,
APIs, and the Java packages that a Java API contains. You also studied Java classes, including nested classes and
inner classes, as the Java packages contain Java classes. You then went the next level down in Java, to the method,
which is like the function in other programming languages, as well as to a special kind of Java method called a
constructor method.
Next, you explored how Java represents data, using fields, or data fields, examining the different types, such as
constants, or fixed data fields, and variables, or data fields that can change their values. After that, you took a closer
look at Java modifier keywords, including the public, private, and protected access control keywords and the final,
static, abstract, volatile, and synchronized nonaccess control modifier keywords.
After finishing with the basic code structures and how to modify them, you moved on to the primary Java data
types, such as boolean, char, byte, int, float, short, long, and double and then explored the Java operators that are
used to process, or bridge, these data types over to your programming logic. You studied arithmetic operators, for use
with numeric values; logical operators, for use with boolean values; relational operators, to consider relationships
between data values; conditional operators, which allow you to establish any conditional variable assignments; and
assignment operators, which let you assign values to (or between) variables.
Then, you looked at Java logic control structures, including decision-making control structures (I like to call
them decision trees) and looping, or iterative, logic control structures. You learned about the Java switch-case
structure, the if-else structure, the for loop structure, and the do-while loop structures. Finally, you examined
Java objects and discovered how to define object attributes, states, and behaviors, using a Java class, methods, and
constructor methods.
In the next chapter, I will give you an overview of the JavaFX multimedia engine, and its classes and capabilities,
as you will be leveraging JavaFX to add media elements to your games, such as images, video, and audio, and to
control your games, using JavaFX object constructs (classes), such as the Stage, Scene, and StackPane.
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