Rails for Java Developers

Book Preface

Ruby on Rails is a full-stack framework for developing web applications. Rails embraces many good ideas that are familiar in the Java world: the Model-View-Controller (MVC) pattern, unit testing, agile development, the ActiveRecord pattern, and many others. At the same time, Rails challenges many standard practices: Instead of miles of XML configuration files, Rails relies on conventions where possible. Rails is built with Ruby, a dynamic language, and is deployed as source code. But forget the technical points for a moment. The reason that any of this matters is that Rails programmers are getting things done, and fast. Rails programmers have made (and substantiated) some amazing claims about developer productivity. They are having a lot of fun, too. Should Java programmers be alarmed by this upstart? Absolutely not. Java programmers are uniquely positioned to take advantage of Ruby on Rails. This book will explain how to get started.

Who Should Read This Book?

This book is for all Java programmers. OK, let us narrow that down a little. This book is for two subsets of Java programmers:

• Those who want to program in Ruby and Rails

• Those who do not

To the first group: We wrote this book because we love Java, and we love Rails. We believe that Java programmers are uniquely qualified to take advantage of Rails, because Java programmers have lived through a lot of the struggles behind the good (and sometimes controversial) ideas in Rails.

To the second group: Rails is not for everything, just like any other tool isn’t. However, Rails is such an interesting tool, and Ruby is different from Java in so many fascinating ways, that we think it is the single best complement you can learn to round out your skill set.

To both groups: We have had a great time writing this book, because we share a common language with you, our readers. By assuming a common vocabulary of the Java language and patterns, we are able to move quickly to the meat of topics. We believe that, page for page, this is a much better book for Java developers than a general-purpose book can ever be. Yes, that’s bragging, and we are boasting about you, our fellow Java developers. Thanks for all the work you have put in to build a baseline of industry knowledge on which we hope to build.

Why This Rails Book?

A lot of Rails books exist. One aspect that sets this book apart is our Java background. We focus on the parts of Rails that will be different, new, and interesting to a Java developer.

The second aspect that sets this book apart is our emphasis on Rails as an ecosystem, not just as a framework. As a Java developer, you are accustomed to having an enormous ecosystem around your programming language. You have great IDEs, monitoring tools, and widgets for every situation. Rails has an ecosystem too—not as big as Java’s but important nevertheless. In this book, we spend less time hashing through every random API detail in Rails. Instead, we demonstrate the key points and then move into the ecosystem to show how those key points are used, extended, and sometimes even replaced.