Frameworks in Catalysis: Pictorial Notation and Formal Semantics

Kung-Kiu Lau
Dept of Computer Science
University of Manchester
Manchester M13 9PL, UK
kung-kiu@cs.man.ac.uk

Mario Ornaghi
DSI, Universita' degli studi di Milano
Via Comelico 39/41, 20135 Milano, Italy
ornaghi@dsi.unimi.it

Alan Wills
Trireme International Ltd
24 Windsor Road
Manchester M19 2EB, UK
alan@trireme.com

Abstract:
In OO Design, it is widely recognised that the distribution of tasks between
objects and the contracts between them are key to effective design. In 
composing designs from reusable parts, the parts are therefore frameworks,
namely descriptions of the interactive relationships between objects which 
participate in the interactions. Designs are then built by composing these 
frameworks, and any object in the final design will play (various) roles from 
several frameworks. Practitioners of OO Design use pictorial notations for 
design. However, in order to reason formally about design, we need a 
sound (formal) semantics for the diagrams. In this paper, we show that
frameworks can be formalised as many-sorted theories, and then present
a pictorial representation of such theories, developed in the
Catalysis project.