Pattern-Based Transformation of Sequence Diagrams Using QVT

Design patterns provide a proven solution for a recurring design problem. There has been much work on tool support for pattern reuse. However, the existing work focuses mostly on the static structure of design patterns, leaving behavioral aspects largely manual. In this work, we present an approach for transforming application behaviors based on behaviors of design patterns using Query/View/Transformation (QVT). In the approach, we specify a design pattern in terms of a problem specification, a solution specification, and a transformation specification at the metamodel level. A problem model that exhibits the behaviors of the problem specification is transformed to a solution model with the behaviors of the solution specification. We use Role-Based Metamodeling Language (RBML) for specifying problem and solution specifications and QVT for describing transformation rules. We demonstrate the approach using the Observer pattern applied to a graph application.