Even with prior writing experience, I never thought writing a book would be such a massive undertaking. I was accustomed to a fast loop between myself and an editor with three or four e-mail exchanges from proposal to finished article. If it took over a thousand exchanges simply to help me shape the content of this book, I wouldn't be surprised.

First off I'd like to acknowledge everyone at Apress. The people involved at the initial stages of the book—when it was just an idea: Steve Anglin, Dominic Shakeshaft, and Joohn Choe. The people with whom I interacted once the book got underway all the way to its end: Kylie Johnston, Tom Welsh, and Matthew Moodie. And the people involved toward the final stages of this project: Ami Knox, Laura Cheu, and Stephanie Parker. And of course, every other person at Apress who had a role in this book with whom I didn't have the opportunity to interact directly.

For helping me to keep the content accurate on the technical front, special thanks go to Gerd Wütherich, who served as the book's technical reviewer, as well as Colin Yates, who initially took part in the technical review process.

In addition, the book would not have been possible without many articles, documents, and blog posts by the people who shape OSGi, Spring, and Spring-DM technology, including Adrian Colyer, Alex Blewitt, Costin Leau, Eric Newcomer, Neil Bartlett, Martin Lippert, Peter Kriens, Rob Harrop, and Rod Johnson. And of course, the many other people active in these areas who surely influenced my thought processes, but whom I unfortunately can't credit individually due to space constraints and the limitations of memory.

And finally, I thank my family and friends. Although did I evoke long blank stares after I tried to explain this book's purpose in layman's terms, but (in what is perhaps the best morale support one could ask for), these same people kept asking me about this project's progress. I would need too much space to do it individually, so to everyone who asked, thank you. I consider you a part of this effort for providing face-to-face moral support.