Part 3. Integrating enterprise OSGi with everything else

Now that we’ve reached part III of our book, it’s time to start looking at how OSGi relates to the environment you already have. Our main focus so far has been developing new applications from scratch. Although we’re sure you’d agree that this is a fun approach, it isn’t realistic to assume that you’ll always be starting with a clean slate. Java has a rich and successful history, and this means that there will be a lot of existing code that you want to use.

Despite our description of the enterprise as a large distributed system in section 1.1.2, your applications so far have been firmly tied to a single virtual machine. You’ll remedy this in chapter 10, where we look at how to extend enterprise OSGi applications between frameworks.

In chapter 11, we consider how to connect OSGi frameworks to non-OSGi containers using SCA and ESBs. We also present suggestions for how to migrate applications running in these non-OSGi containers to OSGi.

In chapter 12, we’ll look at how to use existing Java libraries. You may hit a number of pitfalls using libraries that weren’t designed for OSGi in an OSGi environment, so we’ll explain what to watch out for and how to make everything work.

Finally, we’ll review the available enterprise OSGi servers in chapter 13. Many of the popular application servers support OSGi applications, and you can also assemble a good OSGi stack starting with a simple OSGi container.

By the time we finish this part, our work here will be done, and you should have a thorough mastery of enterprise OSGi. But first, let’s have a look at distributed OSGi.