Introducing fuzziness in object models and database interfaces through aspects

Imperfection in information can be considered a cross–cutting concern that manifests itself in diverse kinds of imprecision, uncertainty or inconsistency in the data models of a software system. The extension of existing programming and querying interfaces for the different aspects of information imperfection requires a proper modularization of the different concerns of numerical imprecision handling, so that the extensions do not interfere with existing programming practices and do not obscure the original design. Aspect–oriented design (AOD) enables such form of non–intrusive extensions to be added to existing software libraries, clearly separating fuzziness or other imperfections in data as a differentiated concern, that can be considered from the early phases of development. In this paper, a general framework for aspect–based extension of data models and fuzzy databases is described, and some design and implementation issues of such AOD–based extensions on OJB database libraries are described as a case study.