[JAVA][Beginning Java 8 Games Development]

Chapter 3 ■ A Java 8 Primer: An Introduction to Java 8 Concepts and Principles
}
} else if(ibState = 'R') {
deathLogicRunning();
} else {
deathLogicIdle();
As you can see, this if-else decision tree structure is quite similar to the switch-case that you created earlier,
except that the decision code structures are nested inside each other rather than contained in a flat structure. As
a rule of thumb, I would use the if and if-else for one- and two-value evaluations and a switch-case for three-value
evaluation scenarios and greater. I use this switch-case structure extensively in my books covering Android.
Next, let’s take a look at the other types of conditional control structures that are used extensively in Java, the
looping programming structures. These allow you to execute a block of programming statements a predefined
number of times (using the for loop) or until an objective is achieved (using a while or a do-while loop).
Looping Control Structures: While, Do-While, and For
Whereas the decision tree type of control structure is traversed a fixed number of times (once all the way through,
unless a break [switch-case] or resolved expression [if-else] is encountered), looping control structures keep
executing over time, which, with respect to the while and do-while structures, makes them a bit dangerous, as an
infinite loop can be generated, if you are not careful with your programming logic! The for loop structure executes for
a finite number of loops (the number is specified in the definition of the for loop), as you will soon see in this section.
Let’s start with the finite loop, covering the for loop first. A Java for loop uses the following general format:
for(initialization; boolean expression; update equation) {
programming statement one;
programming statement two;
}
As you can see, the three parts of the evaluation area of the for loop are inside the parentheses, separated by
semicolons, as each contains a programming statement. The first is a variable declaration and initialization, the
second is a boolean expression evaluation, and the third is an update equation showing how to increment the loop
during each pass.
To move the InvinciBagel 40 pixels diagonally on the screen, along both X and Y, the for loop is as follows:
for(int x=0; x < 40; x = x + 1) { // Note: an x = x + 1 statement could also be coded as x++
invinciBagelX++; // Note: invinciBagelX++ could be coded invinciBagelX = invinciBagelX + 1;
invinciBagelY++; // Note: invinciBagelY++ could be coded invinciBagelY = invinciBagelY + 1;
}
In contrast, the while (or do-while) type of loop does not execute over a finite number of processing cycles, but
rather executes the statements inside the loop until a condition is met, using the following structure:
while(boolean expression) {
programming statement one;
programming statement two;
}
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