OSGi Learning Laboratory

Learn the 3 pillars of OSGi:

• Modularity
• Module lifecycle
• Services
  • Registering and retrieving services
  • Separating programming interfaces from implementations

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Getting Started

Installed on your computer:

• Java 8 JDK
• Git
• Maven

You:

• Basic knowledge of Java, Git, and Maven.
• These instructions assume you are using the IntelliJ IDE

The course is organized into two repositories:

• This repository, named osgi. It provides the lessons and their solutions. The completed lessons are in the src/ folders.
• Another repository named osgi-lessons. It is the skeleton to which you will add files, code, and configuration information.

How to get the most out of this course

Type. Don't copy and paste from the solutions. Maybe here is some tedious stuff you might want to copy and paste, but the more you type it in, the more you will learn. Also, the less you can refer to the solutions, the more you will learn. Challenge yourself to see how little you can look at the completed code.

What you need to do now

The first thing to do is to clone the osgi-lessons repository to the computer you will use for this course.

git clone https://github.com/ahoffer/osgi-lessons.git

The second thing you need to do is open your clone of osgi-lessons in IntelliJ. From IntelliJ, choose

File -> New -> Project From Existing Sources...

and choose the osgi-lessons directory.

Lastly, make sure everything is ready to go. Build the project. Change to the osgi-lessons directory and tell Maven to build:

mvn install

You should see [INFO] BUILD SUCCESS in a few seconds. If not, figure out why before proceeding.

OK. Proceed to lesson 1, Bundles.

Lesson 1: Bundles

• Modularity and life cycle
• Create a bundle
  • Activator class
  • Bundle Context
  • Maven Bundle Plugin
• Install a bundle
• Start, stop, resolve a bundle

Lesson 2: Add a Logger

• Add logging interface as dependency
• Use logging

Lesson 3: OSGi Blueprint

• OSGi Blueprint Specification
• Java beans
• Dependency injection framework

Lesson 4: Create a Service

• Services instead of methods or functions
• Service as POJO

Lesson 5: Consuming a service

• Getting hold of a service programmatically

Lesson 6: API

• Decouple interface from implementation
• Create multiple providers that for the same API

Addtional Resources

• [OSGi Bundles and the maven-bundle-plugin](OSGi Bundles and the maven-bundle-plugin-v4-20180305_Author-Richard_Porter.pdf). Tutorial by Richard Porter. Covers api-implementation separation and helpful dos-and-dont'ts
• OSGi Troubleshooting by Brendan Hofmann