Osgi in a nutshell [note]

Osgi Specification

L an open specification for the delivery of managed services to networked environment.

L osgi services platform: osgi framework & a set of standard service Definitions

 

The osgi framework

L osgi framework: sits on the top of JVM, the excution environment for services

L involves: Services Platform & Deployment infrastructure

 

Services Platform

Software platform that supports the Service Orientation Interaction, involves:

L Service Registry: belongs to the Services Platform

L service provider (bundle): publish service description

L service requester (bundle): Discover service and bind to service provider

 

Bundle

L both a logical as well as physical entity

L JAR file contains code, resources and manifest file (bundle Information)

L responsible for run-time service dependency management activities: publication, disication, binding, adapting to change resulting

 

Deployment infrastructure

L continuous deployment activities: installation, removal, update, starting (activation), stopping (de-activation) of a physical bundle

L The activation or de-activation of a physical bundle results in the creation or destruction of a unique logical bundle, materialized by a bundle activator.

L when the logical bundle is active, can publish or discover services and bind with other bundles, also be notified from changes that occur in the framework by subscribing as an event listener (Service Orientation Interaction ).