Three steps to views: Extending the object-oriented paradigm

Abstract

At the core of any sophisticated software development and maintenance environment is a large mass of complex data. The data (the central data of the environment) is composed of smaller sets of data that can be related in complicated and often subtle ways. The user or developer of the environment will be more effective if they are able to deal with conceptual slices, or views, of the large, complex structure. This paper presents an architectural building block for object-based software environments based on the views concept. The building block allows the construction of global abstractions that describe unified behavior of large sets of objects. The basis of the architecture relies on extending the object-oriented paradigm in three steps: (1) defining multiple interfaces in object classes; (2) controlling visibility of instance variables; and (3) allowing multiple copies of an instance variable to occur within an object instance. This paper focuses on the technical aspects of the views approach.