Jason Dillon wrote:
PS. Can someone write up something about the current state of the major component containers out there with a feature blurb... no soap boxes, just the facts jack.
Based on current directions (and subject to the usual votes within the comming days) the Avalon community is about to release a container framework – codenamed Merlin. The framework deals with a set of critical container/component concerns that provide support for general component models (not just classic Avalon).
In particular, the Merlin framework includes:
* component meta info - declaration of a component criteria including configuration and parameterization requirements, contextualization requirements (including contextualization strategy, casting constraints, context entry requirements, optional and volatile entry criteria, etc.)., service dependencies, general component type attributes, logging criteria, etc.
* component meta data - definition of the meta model for declaration of component deployment directives that instruct a container with respect to deployment requirements - things like activation policies, configuration and contextualization information to be applied to components, lifecycle and lifestyle management and so on.
Combining the above two models together in a runtime environment enables the establishment of a model driven containment solution (the composition framework). Meta info and meta data can be supplied in either XML or serializable form, enabling remote model execution and management. Model execution is realized though the Merlin 'activation' platform which provides the infrastructure for nested component hierarchies, composite components (container that contain components the define an implementation strategy that allows a container to publish itself as a component), and the complete framework for configuration and context management based on a model driven approach. The Avalon work has already started on a JMX solution and with the introduction of the activation API, the Merlin platform will be able deliver a very significant level of management automation exposed via local or remotely accessible JMX management points that reach into fine-grain controls within the containment model.
Aside from all of the above - the Merlin platform provides a neutral component type discovery system and an automated component assembly framework. This ensures that the overall component deployment process can be simplified dramatically, in some cases down to nothing more than a couple of container directives.
The first public release of the Merlin platform should be coming out of Avalon within a matter of days. From there on the Avalon community will be leveraging the Merlin platform as the generic framework on which a new model-driven solutions will be delivered. I'll try to make sure we get release info to you as soon as it becomes available.
Cheers, Steve.
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Stephen J. McConnell mailto:[EMAIL PROTECTED] http://www.osm.net
Sent via James running under Merlin as an NT service. http://avalon.apache.org/sandbox/merlin
