1.4: The Form of a Reengineering Pattern

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Page ID: 32360

Serge Demeyer, Stéphane Ducasse, Oscar Nierstrasz
University of Antwerp, INRIA Lille, University of Bern

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In Figure 1.5.1 we see an example of a simple pattern that illustrates the format we use in this book. The actual format used may vary slightly from pattern to pattern, since they deal with different kinds of issues, but generally we will see the same kind of headings.

The name of a pattern, if well-chosen, should make it easy to remember the pattern and to discuss it with colleagues. (”I think we should Refactor to Understand or we will never figure out what’s going on here.”) The intent should communicate very compactly the essence of a pattern, and tell you whether it applies to your current situation.

Many of the reengineering patterns are concerned with code transformation, in which case a diagram may be used to illustrate the kind of transformation that takes place. Typically such patterns will additionally include steps to detect the problem to be resolved, as well as code fragments illustrating the situation before and after the transformation.