OSGI / Equinox ?

[kri shan]

OSGI is a technology for creating code in an SOA framework (a coding framework). Complex Service Oriented architecture supports OSGi as the foundation for its next generation runtime infrastructure.

Why do we need another SOA runtime framework ? Already Axis2 / Spring Web Services are supporting SOA coding frameworks.

Equinox is an implementation of the OSGi R4 core framework specification, a set of bundles that implement various optional OSGi services and other infrastructure for running
OSGi-based systems.
The goal of the Equinox project is to be a first class OSGi community and foster the vision of Eclipse as a landscape of bundles. As part of this, it is responsible for
developing and delivering the OSGi framework implementation used for all of Eclipse.

What Equinox does (still i am not clear) ? Is it Eclipse plug-in for OSGI framework support ?

[Stuart McCulloch]

kri shan wrote:

OSGI is a technology for creating code in an SOA framework (a coding framework). Complex Service Oriented architecture supports OSGi as the foundation for its next generation runtime infrastructure.

Why do we need another SOA runtime framework ? Already Axis2 / Spring Web Services are supporting SOA coding frameworks.

OSGi is a layered framework (module, lifecycle, services) which means you don't have to use all the layers - if you just want modularity then you can focus on that layer and ignore the lifecycle and service layers. While the SOA-like service layer was developed a long time before SOA was defined, you could think of it as SOA inside the JVM. And thanks to the efforts of the Enterprise OSGi Expert Group you can now integrate distributed SOA runtimes like Axis2 with OSGi.

kri shan wrote:

Equinox is an implementation of the OSGi R4 core framework specification, a set of bundles that implement various optional OSGi services and other infrastructure for running OSGi-based systems. The goal of the Equinox project is to be a first class OSGi community and foster the vision of Eclipse as a landscape of bundles. As part of this, it is responsible for
developing and delivering the OSGi framework implementation used for all of Eclipse.

What Equinox does (still i am not clear) ? Is it Eclipse plug-in for OSGI framework support ?

Equinox is the reference OSGi framework. It is also the foundation of the Eclipse runtime - so when you install Eclipse plugins you're installing them on Equinox.

[Richard S. Hall]

kri shan wrote:
Why do we need another SOA runtime framework ? Already Axis2 / Spring Web Services are supporting SOA coding frameworks.

To be very clear, OSGi is not an SOA framework. It promotes a service-oriented interaction pattern for collaboration among modules, since this promotes loose coupling which is good programming practice. But there is nothing in the OSGi framework that relates to Web Services other than the logical concept of a service. As Stuart points out, these concepts in OSGi pre-date web services.

[Augusto Sellhorn]

Richard S. Hall wrote:
To be very clear, OSGi is not an SOA framework. It promotes a service-oriented interaction pattern for collaboration among modules, since this promotes loose coupling which is good programming practice. But there is nothing in the OSGi framework that relates to Web Services other than the logical concept of a service. As Stuart points out, these concepts in OSGi pre-date web services.

Good point. I think people confuse SOA with web services, or other technologies to implement services (or routing like ESB). But at the very core OSGi is SOA in the best generic sense of the definition. In my view, the most powerful part of OSGi is defining services as Java interfaces and looking them up dynamically, via filters ,with multiple implementations, etc.