A framework for dynamic evolution of object-oriented specifications

It is noted that the evolution of specifications is necessary to accommodate the evolution of requirements and design decisions during the software development and maintenance process. The authors are concerned with formal description techniques that allow the development of executable specifications, especially executable object-oriented specifications of distributed systems. They propose a two-level model for the evolution of large object-oriented specifications. The first level deals with the dynamic modification of types (classes) while the second level deals with the modification of modules. To allow for dynamic modification of types and modules, the authors have developed a reflection-based technique using meta-objects in which the modification operations are defined. In their approach, they have defined a set of structural and behaviour constraints to ensure the specification consistency after its modification at both levels