[JAVA][Beginning Java 8 Games Development]

Chapter 3 ■ A Java 8 Primer: An Introduction to Java 8 Concepts and Principles
To code the for loop to move the InvinciBagel 40 pixels, using a while loop structure, looks like this:
int x = 0;
while(x < 40) {
invinciBagelX++;
invinciBagelY++;
x++
}
The only difference between a do-while loop and a while loop is that, with the latter, the loop logic programming
statements are performed before, instead of after, the evaluation. Thus, using a do-while loop programming
structure, the previous example would be written as follows:
int x = 0;
do {
invinciBagelX++;
invinciBagelY++;
x++
} while(x < 40);
As you can see, the Java programming logic structure is inside curly braces, following the Java do keyword,
with the while statement after the closing brace. Note that the while evaluation statement (and therefore the entire
construct) must be terminated with a semicolon.
If you want to make sure that the programming logic inside the while loop structure is performed at least one
time, use the do-while, as the evaluation is performed after the loop logic is executed. If you want to make sure that
the logic inside the loop is only executed after (whenever) the evaluation is successful, which is the safer way to code
things, use the while loop structure.
Java Objects: Virtual Reality, Using Java Constructs
I saved the best, Java objects, for last, because they can be constructed in one fashion or another using all the concepts
that I have covered thus far in the chapter and because they are the foundation of OOP language (in this case, Java 8).
The fact is, everything in the Java 8 programming language is based on Java’s Object superclass (I like to call it the
masterclass), which is in the java.lang package, so an import statement for it would reference java.lang.Object, the full
pathname for the Java Object class.
Java objects are used to “virtualize” reality by allowing the objects you see all around you in everyday life, or,
in the case of your game, objects you are creating out from your imagination, to be realistically simulated. This is
done by using the data fields (variables and constants) and the methods that you have been learning about in this
chapter. These Java programming constructs will make up the object characteristics, or attributes (constants); states
(variables); and behaviors (methods). The Java class construct organizes each object definition (constants, variables,
and methods) and gives birth to an instance of that object, using the constructor method for the class that designs and
defines the object via the various Java keywords and constructs.
Creating an InvinciBagel Object: Attributes, States, and Behavior
Let’s put together an example of an InvinciBagel object that shows how constants define characteristics, variables
define states, and methods define behaviors. We will do this using Java coding constructs that you have learned about
thus far in the chapter, including constants, variables, and methods that you have already defined, to some extent.
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