You probably picked up this book because of the buzzwords Ajax, REST, and patterns. You will
probably read this introduction and skim through the pages. But I want to stop you from skimming
through the pages, at least for a moment. I want you to read this introduction and then decide
whether you want to buy the book.
Here are the things you need to know about Ajax:
? Ajax is an acronym, and the ramifications of the acronym are immense.
? Ajax is not just about a fat client, JavaScript, XML, or asynchronous behavior, but about
developing the next generation of web applications.
? We are at the beginning of building the next generation of web applications.
You are still reading, and that means I still have your interest, which is a good thing. So now
let me tell you what this book is about:
? Using Ajax is the act of creating a web application that implies using REST, that implies
using HTTP, and that implies using the Internet. The patterns of this book illustrate how
JavaScript can be used to control the XMLHttpRequest object to make XMLHttpRequest calls
that process XML or HTML.
? This book for the server side focuses on using Java and C# .NET. The patterns can be used
with Python or Ruby on Rails. I focus on Java and C# because at the time of this writing I
feel that most developers are using them. In the next edition of this book, I want to extend
the materials to include Python and Ruby on Rails examples, because I happen to be an
avid Python programmer.
? The patterns in this book can be used in other contexts, such as Flex (Flash Ajax). For
example, the Permutations pattern can be used to generate Flex content.
Good, you’re still reading and haven’t closed the book. That means you are still interested
and probably willing to spend a few more moments. Here is what I suggest: finish reading the
Introduction because it includes a road map of the patterns. Skim Chapter 1 to get an idea of
what Ajax does and is. Then skim the patterns and focus on reading the “Motivation” and
“Architecture” sections.

■CHAPTER 1 Introduction to Ajax . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
■CHAPTER 2 The Nuts and Bolts of Ajax . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
■CHAPTER 3 Content Chunking Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
■CHAPTER 4 Cache Controller Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
■CHAPTER 5 Permutations Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
■CHAPTER 6 Decoupled Navigation Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 153
■CHAPTER 7 Representation Morphing Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . 197
■CHAPTER 8 Persistent Communications Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . 225
■CHAPTER 9 State Navigation Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 265
■CHAPTER 10 Infinite Data Pattern . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 303
■CHAPTER 11 REST-Based Model View Controller Pattern . . . . . . . . . . . . . . . . . . 333