Talbot Tim. - Another Introduction to Programming with Java Book

Shortly following my initial studies of HTML, I ventured deeper into the workings of the internet and deciphered tools and concepts unknown and new to me such as web servers, databases and server side scripting. My point is, as a child trying to learn these technologies I never really managed to grasp anything the first time round and always felt that they could be explained much more clearly; for example, it took me several attempts with plenty of time off in between to fully comprehend just how to go about running a local web server. Port forwarding was a nightmare! Perhaps this is the reason many non-fiction authors put pen to paper nowadays, I guess! Following my web development ventures, I moved on to C++ and found console (command line) applications quite interesting, especially once I moved past the simple stuff and started touching on object oriented programming (OOP). I decided to start learning Java the first time round when I hit pointers in C++ as they were such a horrid concept to wrap my head around at the time. Java was easy enough to pick up as the syntax is not unlike the syntax of C++. Of course, there was some Visual Basic thrown in there somewhere but I like to pretend I've never heard of it! Pretty much all programming related work at university was based on Java.

This has resulted in upwards of 12 years of self study followed by 3 years of professional education and over that length of time I have gained a great understanding of Java and programming in general. So, in essence, the reason I decided to write this book was to hopefully provide you with a much more concise, organised and clear way of learning the basics of programming with Java in a way that I wish was available to me at the time I began learning the language. My intentions were to convey the core concepts of Java as best I can with as little content as possible, getting straight to the point without too much crap in between, in order to make the book a quick read without missing anything important. A difficult compromise to reach and I hope I've done it right for you guys!

Who this book is for

This book is for anyone wanting to learn Java. Whether you're a beginner and have no knowledge of programming whatsoever, or you're an intermediate Java programmer and want to better understand some of the more advanced topics in this book, this book is for you. It's written with the beginner in mind but segmented in a way that means that the example code and exercises don't make you go searching through previous chapters to understand what's going on, unless you need to know what's going on!

Conventions used in this book

When referring to names of classes, variables, methods or keywords I will use italic font unless I forget; I'm only human! If you see this heading then there are some simple exercises for you to do relating to the information you've just read.

Of course, nobody is forcing you to do them (unless you have a Jedi next to you working some mind tricks, but this isn't ideal) but they are intended to help you further understand the information they are being applied to. Solutions to these exercises can be found at the back of the book if answers are needed. I know, it's a pain in the ass and always drives me crazy too but what's the point in having a challenge if the answer is on the same page?! I will aim to include these exercises at the end of every key topic and, naturally, they will gradually increase in time consumption and difficulty. If you see this heading then you should take a few moments to study the points following it and make sure you understand them clearly. Similarly to the exercises, these will gradually increase in complexity but I will explain them in each section as clearly as possible. There will be many times I just spam you with pages of code.

Don't be disheartened, copy it out and compile it (I check every piece of source code before introducing it to the book to ensure it works so if it doesn't and you're sure you've got it right, email me!) and seek to understand it. The methodology is to give you the code and then explain it once you've written it out and tried it for yourself. That way, you will have at least a partial understanding of it before I dissect it piece by piece. Sometimes I may do it backwards, depending on what topics I'm discussing. Finally, you will notice a lot of tables in the beginning of this book - this is because tables are the most effective and clear way of presenting information that can be found easily and referred back to when needed.

Problems with this book

At the end of this book lies an email address, this can be used to report any errors, typos or other problems with this book if you stumble across such problems.

If there are indeed errors, they will be put on my website at: http://timtalbot.co.uk/aitpwjb/ aitpwjb = Another Introduction to Programming with Java Book, in case you're curious like me. The purpose of this is to ensure that you're not running into problems whilst reading through the book, because I've read books with errors in the past and let's face it, they suck!

Chapter 2: Where to Begin

Quick Overview

I'm sure that you all know what Java is and the applications of it, but if not - here's a quick overview. Java is a programming language that first came to light in 1995. It takes much of its syntax from C and C++ and was created with the specific intention of eradicating as many implementation dependencies as possible. It is an object oriented language and is completely platform independent. This is because, unlike, say, a native C++ program compiled on the platform it is intended for where the compiler translates source code directly into machine code, when Java is compiled the source is converted into class files containing byte code which is then interpreted by the Java Virtual Machine (JVM) on whatever platform the class file is run on.