A powertype-based metamodelling framework

Abstract

Software development methodologies may be described in the context of an underpinning metamodel, but the precise mechanisms that permit them to be defined in terms of their metamodels are usually difficult to explain and do not cover all needs. For example, it is difficult to devise a way that allows the definition of properties of the elements that compose the methodology and, at the same time, of the entities (such as work products) created when the methodology is applied. This article introduces a new approach to constructing metamodels and deriving methodologies from them based on the concept of powertype. It combines key advantages of other metamodelling approaches and allows the seamless integration of process, modelling and documentational aspects of methodologies. With this approach, both methodology components and project entities can be described directly by the same metamodel.

DeepTelos: Multi-level Modeling with Most General Instances

“…Adding to a metaclass c an MGI m results in a base class m with a power type c. The contribution of DeepTelos is to fully integrate this construct in a metamodeling language and system which already comes with support for unbounded deep characterization via 'mediated' [20] properties and full support for metaclasses. This also sets DeepTelos apart from work on the powertype pattern [4] where the powertype role is played by a 'normal' class. For an insightful analysis of power types and their role in multi-level modeling see [3].…”

“…In classical two-level models, one would have to separate the class and object flavors into different objects, e.g. using the powertype pattern [4]. Multi-level modeling aims at avoiding this separation by regarding each class also as an object that can have its own properties.…”

Dual Deep Instantiation and Its ConceptBase Implementation

“…VODAK [15] was the first system to introduce what was later called deep instantiation/characterization [17,8]. The capability of deep instantiation was achieved by VODAK in that objects where in parallel to types also organized into classes and meta-classes.…”

“…The capability of deep instantiation was achieved by VODAK in that objects where in parallel to types also organized into classes and meta-classes. Meta-classes defined own-types, instance-types and instance-instancestypes, basically representing a cascading structure of what later became known as power type design pattern [8]. Type instantiation is between an object and its class's instance type and is inferred from the functional association of an object to a class to provide for a lossless and redundancy-free representation of functional data dependencies according to database design theory.…”

A formalisation of deep metamodelling

“…In this approach, a system is specified using models at two metalevels: a metamodel defining allowed types and a model instantiating these types. However, this approach may have limitations [AK02b,AK08,GPHS06], in particular when the metamodel includes the type-object pattern [AK02b,AK08,GPHS06], which requires an explicit modelling of types and their instances at the same metalevel. In this case, deep metamodelling (also called multi-level metamodelling) using more than two metalevels yields simpler models [AK08].…”