Modular Java: Creating Flexible Applications with OSGi and Spring is one of the first OSGi books hitting the shelves this year, and probably the most practical and simple book on server-side OSGi published so far. The author (Craig Walls) adopts a really pragmatic approach here: the OSGi specification is covered only in its fundamental aspects, and most part of the book is spent discussing tools and methods to simplify OSGi application development. That considered, the book target is probably not the OSGi absolute beginner, who will benefit more from reading a book like OSGi in Practice (or the specification itself), but the OSGi practitioner who wants to start developing its OSGi application the right way. Needless to say, also more experienced developers will learn quite a few tricks from these pages.

Let’s now examine the book in more details.


Coverage of the OSGi specification

The book just covers the basics of the Core specification (bundles, modularity, services, fragments) and only a few of the Compendium services (Configuration Admin Service, just a few words on the HTTP Service and the upcoming Blueprint service). Therefore, a basic OSGi knowledge is required to fully understand the contents of the book.


Coverage of OSGi tools

The real value added of this book is the description of a complete “OSGi development method” that covers the development, packaging, configuration and management of an application. This method takes advantage of several tools, that are clearly described in the book

• Pax Construct
• Pax Runner
• Pax Exam
• Pax ConfMan
• Maven
• Apache Felix Web Console

Another big topic in this book is Spring Dynamic Modules, which is explained in good detail in Chapter 6 and 7.


Example Application

The example application is a quite interesting Jar search engine built on top of Spring, Spring DM and Compass. Not all the code is explained in the book, but everything can be downloaded from the book website.


Conclusion

As remarked before, that’s not a book for OSGi beginners. The reader must be already familiar with OSGi development and the OSGi specification.
On the other side, the OSGi practitioners will find particularly interesting the hard work that Craig has put in trying to simplify OSGi development, and his adoption of Pax tools to make the process as smooth as possible.
The book is also a good starting point for those interested in learning Spring DM.
Highly recommended.

• Building OSGi application with Maven
• Groovy Maven
• Scala and Maven

Read the book here. A pdf download is also available.

Modular Java: Creating Flexible Applications with OSGi and Spring, by Craig Walls
I totally missed this title last February, but it seems Craig and the Pragmatic Programmers have been very quick to develop and publish this book. They were kind enough to give me a copy, so expect a more detailed review in the next few weeks.
Read the Modular Java review here

Pro Spring Dynamic Modules for OSGi™ Service Platforms, Apress, by Daniel Rubio
Available; the table of contents looks interesting (quite original the Flex with OSGi chapter) , but I haven’t had any time to look at it.
Dowload the table of contents

OSGi in Practice, by Neil Bartlett
No big news on this side, the book is not complete yet, but it’s free, and it’s, in my opinion, the most well-written book on the topic.
Donwload it here

OSGi in Action, Manning, by Richard S. Hall, Karl Pauls, Stuart McCulloch and Davide Savage
Very promising title, but its development is particularly slow. They gained an additional author (David Savage of Paremus), and the new estimated release date is January 2010; at the moment only a few chapters are available.
I have subscribed the Manning MEAP (Early access program), so I’ll keep you updated on its development
Table of contents (HTML)

Die OSGi Service Platform, Dpunkt.Verlag, by Gerd Wütherich, Nils Hartmann, Bernd Kolb, Matthias Lübken
German only! I had a good look at it in a local bookstore, and it seems very complete but also very Equinox-centric; a good reference if you speak enough German.
Table of contents (pdf)

Equinox and OSGi: The Power Behind Eclipse, Addison Wesley, by Jeff McAffer, Paul VanderLei, Simon Archer
Initially announced for August 2009, the release date has moved to end of November. No preview is available, as far as I know. Preview available on Safari.

OSGi Application Frameworks, Manning, by Alexandre de Castro Alves
New title from Manning, just entered in the MEAP program. Expected release, January 2010
Details here (HTML)

Spring Dynamic Modules in Action, Manning, by Arnaud Cogoluegnes, Thierry Templier, and Andy Piper
Again Manning, just two chapters available, release February 2010
Details here

In brief, the situation is evolving quite quickly, and hopefully by the beginning of 2010 we’ll be able to see many OSGi books in our bookstores. The Pragmatic Programmers have been quick to move into this (relatively) new topic, and Manning is following with an interesting number of new releases. Apart from Apress, other publishers are probably still waiting to see how this market evolves; particularly strange the lack of titles from O’Reilly.

OSGi in Practice, by Neil Bartlett
Not complete yet, but it’s free, and it’s, in my opinion, the most well-written book on the topic. Donwload it here

OSGi in Action, Manning, by Richard S. Hall, Karl Pauls, and Stuart McCulloch
I bought it, but it’s a preview version; only a few chapters are available.

Die OSGi Service Platform, Dpunkt.Verlag, by Gerd Wütherich, Nils Hartmann, Bernd Kolb, Matthias Lübken
German only! I hope to able to read it, in the future, when my German is improved

Equinox and OSGi: The Power Behind Eclipse, Addison Wesley, by Jeff McAffer, Paul VanderLei, Simon Archer
To be released in August 2009

Pro Spring Dynamic Modules for OSGi™ Service Platform, Apress, by Daniel Rubio
To be release in February 2009