In developing a transformation for a particular design pattern we naturally wish to reuse our previous efforts as much as possible. To obtain maximum leverage, this reuse should be at the highest level possible. Examining the existing design pattern catalogues , it is clear that certain motifs occur repeatedly across the catalogues. For example, a class may know of another one only via an interface, or the messages received by an object may be delegated to a component object for detailed processing. These design motifs, or minipatterns, are combined in various ways to produce different design patterns. In this way, a pattern can be viewed as a composition of minipatterns. By focusing on developing transformations for minipatterns, we are able to develop a library of useful transformations that can be reused whenever that minipattern is identified again in a later development. The transformation that corresponds to a minipattern is naturally called a minitransformation.
Contact the author.© Mel Ó Cinnéide 2000