Book Image

Learning Java by Building Android Games - Second Edition

By : John Horton
Book Image

Learning Java by Building Android Games - Second Edition

By: John Horton

Overview of this book

Android is one of the most popular mobile operating systems presently. It uses the most popular programming language, Java, as the primary language for building apps of all types. However, this book is unlike other Android books in that it doesn’t assume that you already have Java proficiency. This new and expanded second edition of Learning Java by Building Android Games shows you how to start building Android games from scratch. The difficulty level will grow steadily as you explore key Java topics, such as variables, loops, methods, object oriented programming, and design patterns, including code and examples that are written for Java 9 and Android P. At each stage, you will put what you’ve learned into practice by developing a game. You will build games such as Minesweeper, Retro Pong, Bullet Hell, and Classic Snake and Scrolling Shooter games. In the later chapters, you will create a time-trial, open-world platform game. By the end of the book, you will not only have grasped Java and Android but will also have developed six cool games for the Android platform.
Table of Contents (30 chapters)
Learning Java by Building Android Games Second Edition
Contributors
Preface
Index

If they come over the bridge shoot them


As we saw in the previous chapter, operators are used in determining whether and how often a loop should execute the code in its body.

We can now take things a step further. Let's look at putting the most common operator == to use with the Java if and else keywords then we can start to see the powerful yet fine control that they offer us.

We will use if and a few conditional operators along with a small story to demonstrate their use. Next follows a made up military situation that is kind of game-like in its nature.

The captain is dying and, knowing that his remaining subordinates are not very experienced, he decides to write a Java program to convey his last orders after he has died. The troops must hold one side of a bridge while awaiting reinforcements.

The first command the captain wants to make sure his troops understand is this:

If they come over the bridge, shoot them.

So how do we simulate this situation in Java? We need a Boolean variable isComingOverBridge...