Pattern Reification as the Basis for Description-Driven Systems

TL;DR

This paper introduces a pattern-based, description-driven system architecture that extends UML to better handle system change and evolution through multi-layered meta-modeling and reusable design patterns.

Contribution

It proposes a novel DDS architecture with explicit dynamic data relationships, five practical design patterns, and a fundamental Graph pattern for structural encoding, demonstrated via the CRISTAL project.

Findings

The architecture captures static and dynamic system behaviors effectively.

Five essential design patterns are identified and encoded.

The CRISTAL project exemplifies system evolution management.

Abstract

One of the main factors driving object-oriented software development for information systems is the requirement for systems to be tolerant to change. To address this issue in designing systems, this paper proposes a pattern-based, object-oriented, description-driven system (DDS) architecture as an extension to the standard UML four-layer meta-model. A DDS architecture is proposed in which aspects of both static and dynamic systems behavior can be captured via descriptive models and meta-models. The proposed architecture embodies four main elements - firstly, the adoption of a multi-layered meta-modeling architecture and reflective meta-level architecture, secondly the identification of four data modeling relationships that can be made explicit such that they can be modified dynamically, thirdly the identification of five design patterns which have emerged from practice and have proved essential in providing reusable building blocks for data management, and fourthly the encoding of the structural properties of the five design patterns by means of one fundamental pattern, the Graph pattern. A practical example of this philosophy, the CRISTAL project, is used to demonstrate the use of description-driven data objects to handle system evolution.