OSGI FRAMEWORK

OSGI and Apache Sling:
OSGI:

• Osgi is a dynamic module system for the Java that provides within which small, reusable,     standardized components  composed into an application and deployed.
• Complete understanding of the OSGI design patterns can be seen here: http://www.computepatterns.com/osgi-design-patterns/ 

Apache Sling:

• It is designed to expose the JCR  through an HTTP based REST API.
• AEM's native functionality and functionality of any website built with AEM are delivered through this framework.

OSGI module system allows to building applications as a set of reloadable and strongly encapsulated services.

OSGI bundles run inside OSGI container. This container manages relations among bundles, which are JAR files that contain extra metadata indicating what services they require and which they provide.

OSGI Specifications enable:

• Modularization by use of a development model where applications are (dynamically) composed of many different(reusable) components.
• Components to hide their implementations from other components while communicating through services, which are objects specifically shared between components. 

OSGI Services:

http://www.knopflerfish.org/osgi_service_tutorial.html 

                                                                                                      (To be Updated...)

Citations:

http://www.aemcq5tutorials.com/tutorials/aem-osgi-configuration-implementation/
SCR Annotations:
http://felix.apache.org/documentation/subprojects/apache-felix-maven-scr-plugin/scr-annotations.html