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

Managing and understanding memory


In Chapter 4, Structuring Code with Java Methods we learned a bit about references. Here is a quick recap

Note

… known as a reference type. They quite simply refer to a place in memory where storage of the variable begins but the reference type itself does not define a specific amount of memory used. The reason for this is straightforward.

We don't always know how much data will be needed to be stored in it until the program is executed.

We can think of Strings and other reference types as continually expanding and contracting storage boxes. So, won't one of these String reference types bump into another variable eventually?

As we are thinking about the device's memory as a huge warehouse full of racks of labeled storage boxes, then you can think of the DVM as a super-efficient forklift truck driver that puts the distinct types of storage boxes in the most appropriate places.

And if it becomes necessary, the DVM will quickly move stuff around in a fraction of...