What are Eclipse Virgo and Eclipse Gemini?

[Hussein Baghdadi]

Hi,
What are Eclipse Gemini and Eclipse Virgo?
Sometimes, Eclipse definitions are too theoretical.
Thanks.

[Richard S. Hall]

John Todd wrote:Hi,
What are Eclipse Gemini and Eclipse Virgo?
Sometimes, Eclipse definitions are too theoretical.
Thanks.

I'm not involved in Eclipse at all, so my descriptions might not be totally accurate.

Eclipse Gemini is about creating enterprise-oriented modules. It is implementing some of the OSGi Enterprise specs, like Blueprint and Web Applications.

Eclipse Virgo was SpringSource's OSGi-based App Server project, which was contributed to Eclipse.

[Sai Hegde]

Eclipse Gemini BluePrint is a implementation of the OSGi Blueprint

[Hussein Baghdadi]

Richard S. Hall wrote:

John Todd wrote:Hi,
What are Eclipse Gemini and Eclipse Virgo?
Sometimes, Eclipse definitions are too theoretical.
Thanks.

I'm not involved in Eclipse at all, so my descriptions might not be totally accurate.

Eclipse Gemini is about creating enterprise-oriented modules. It is implementing some of the OSGi Enterprise specs, like Blueprint and Web Applications.

Eclipse Virgo was SpringSource's OSGi-based App Server project, which was contributed to Eclipse.

Things are fuzzy to me now.
I have basic and primitive idea about OSGi but what is OSGi Enterprise Specs? what is a blueprint?

[Richard S. Hall]

John Todd wrote:
Things are fuzzy to me now.
I have basic and primitive idea about OSGi but what is OSGi Enterprise Specs? what is a blueprint?

The term OSGi is ambiguous since it can refer to the technology, the specs, or the organization (OSGi Alliance).

To be very precise, the OSGi Alliance defines the OSGi Service Platform specification.

The Service Platform specification is actually divided into two specifications: core and compendium. The core spec defines framework-related functionality. The compendium spec (generally) defines reusable services (i.e., standard API).

The core and compendium specifications themselves are not actually monolithic specs, but are actually further divided into (sub-)specifications that address specific areas (e.g., UPnP, JPA, JMX, etc.).

Some of the compendium specifications are related to specific domains (e.g., enterprise or mobile telephony). To signify which specs are related to which domains, the OSGi Alliance effectively defines spec "profiles". The Enterprise Spec is just a profile of the compendium specs related to enterprise applications. The main reason for doing this is that it allows the OSGi Alliance to highlight the use cases for its specs, but it also allows the specs to have different release cycles, since it is not necessary to release the entire compendium to release a new enterprise spec. You can release the enterprise spec first and then just roll the changes into the next compendium spec. Overall, it is a little confusing, but in the end it really is just the core and compendium specs which combine to form the Service Platform spec.

Blueprint is one of the enterprise-related compendium specs, which is an OSGi-standardized version of Spring DM.

[Stuart McCulloch]

John Todd wrote:

Richard S. Hall wrote:

John Todd wrote:Hi,
What are Eclipse Gemini and Eclipse Virgo?
Sometimes, Eclipse definitions are too theoretical.
Thanks.

I'm not involved in Eclipse at all, so my descriptions might not be totally accurate.

Eclipse Gemini is about creating enterprise-oriented modules. It is implementing some of the OSGi Enterprise specs, like Blueprint and Web Applications.

Eclipse Virgo was SpringSource's OSGi-based App Server project, which was contributed to Eclipse.

Things are fuzzy to me now.
I have basic and primitive idea about OSGi but what is OSGi Enterprise Specs? what is a blueprint?

The OSGi Enterprise specs define (optional) APIs, schemas, and services for using OSGi in Enterprise Java. It sits alongside the OSGi Compendium specs that define additional (non-core, non-enterprise) APIs, schemas, and services - which themselves build on the OSGi Core specs. The Alliance tries to keep the core lean and mean by using in-process services to add functionality, which is why the org.osgi.framework package only contains a handful of classes.

Blueprint is the new name for Spring Dynamic Modules which was turned into an official standard by the Alliance - it defines an XML schema for describing service components, which the Blueprint bundle then manages at runtime. This developerWorks article provides a good introduction: http://www.ibm.com/developerworks/opensource/library/os-osgiblueprint/

[Mike Keith]

Allow me to add a few extra words around Gemini.

Gemini is an Eclipse project with a goal of enabling modularization in standard enterprise technologies. It is composed of a number of subprojects, each devoted to a specific technology. As was already mentioned, Blueprint is one subproject; Web (servlets), JPA and JDBC are others. You can read more about it here and you can ask questions on the Gemini Forum if you want to know more.

-Mike
Gemini Project Lead