Design of class hierarchies based on concept, (Galois) lattices

Abstract

Building and maintaining the class hierarchy has been recognized as an important but one of the most difficult activities of object-oriented design. Concept (or Galois) lattices and related structures are presented as a framework for dealing with the design and maintenance of class hierarchies. Because the design of class hierarchies is inherently an iterative and incremental process, we designed incremental algorithms that update existing Galois lattices as the result of adding, removing, or modifying class specifications. A prototype tool incorporating this and other algorithms has been developed as part of the IGLOO project, which is a large objectoriented software engineering joint research project involving academic and industrial partners. The tool can generate either the concept lattice or several variant structures incrementally by incorporating new classes one by one. The resulting hierarchies can be interactively explored and refined using a graphical browser. In addition, several metrics are computed to help evaluating the quality of the hierarchies. Experiments are presented to better assess the applicability of the approach.

Improving Generalization Level in UML Models Iterative Cross Generalization in Practice

“…The class hierarchies of those projects consist of a few dozens of classes and the number of new UML elements 4 A joint project of France Télécom, SOFTEAM and LIRMM supported by the French department of research and industry (RNTL); http://www.lirmm.fr/˜macao. 5 See the web site at: http://www.iro.umontreal.ca/Ú galicia.…”

“…Formal Concept Analysis (FCA) has already been successfully applied to the analysis [1] and restructuring [2][3][4][5][6][7] of conceptual class models: it helps reach optimal hierarchical organization of the initial classes by discovering relevant new abstractions. However, providing far-reaching abstraction mechanisms requires the whole feature set of UML to be covered, inclusive those encoding relational information (e.g., UML associations), whereas such features clearly outgrow the scope of standard FCA.…”

“…In the context of the MACAO project 4 is the formal context on associations. As we have chosen in our first experiments to consider binary directed associations, the two association ends are called…”

Reusing and Composing Tests with Traits

“…We selected them for the following reasons: (i) they are complex and essential parts of a Smalltalk system, (ii) they mix subtyping with subclassing, (iii) they are industrial quality class hierarchies that have evolved over 15 years, and (iv) they have been studied by other researchers [13,6,11,4]. We identified the problems cited above in the Squeak open-source Smalltalk [12].…”

XRay views: understanding the internals of classes

“…Dekel uses CA to visualize the structure of classes and to select an effective order for reading the methods [4]. Godin and Mili [7] applied concept analysis to maintain, understand and detect inconsistencies in the Smalltalk Collection hierarchy. In C++ and Java, Snelting and Tip [12] analysed a class hierarchy by making the relationship between methods and variables explicit.…”