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ISO-TC211 / 19115-2Revision

Repository for sharing documents, models, and schemas for the revision of ISO 19115-2 Metadata extension for Imagery and gridded data
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Extensibility model #15

Open dr-shorthair opened 9 years ago

dr-shorthair commented 9 years ago

There are limitations in how to manage extensions in UML. Either some generic hook needs to be built into the class that is expected to be extended, or extension requires new classes specialized from the original class.

This is much easier in both XSD (though 'Any' and anyType) which enable extension at the instance level, and in the RDF environment (where there is no limitation on adding new properties to old classes, subject to entailments following from property domain axioms).

Should we use UML rigorously, or just as a visual tool?

jetgeo commented 9 years ago

We shall definitely use UML as a modelling tool, not just as a visual tool. The advantages of model driven architecture is much bigger then the limitations regarding extensions. The goal for the standard must be to fulfil most use cases, so that extensions will not be necessary. In cases where extensions will be needed, you can still create your own extensions to the xml schemas.