Pattern Oriented Software Architecture Volume 5: On Patterns and Pattern Languages

8 Pattern Collections

Science is facts; just as houses are made of stones, so isscience made of facts; but a pile of stones is not a houseand a collection of facts is not necessarily science.

Henri Poincaré

The previous chapters have explored how patterns can connect to form a design and inform the activity of design. This chapter looks at the general issue of collecting, organizing, and considering many patterns together, in part in response to the challenge of how a handbook of software architecture might be assembled. The theme of this chapter is pattern collections and catalogs, which act as repositories of patterns. In helping to organize such repositories, we also explore problem frames as a technique for capturing the context and problems in which patterns may be applied, and examine a semiotic perspective on pattern structure and relationships.

8.1 Toward a Handbook

Patterns are gregarious by nature. Any significant design will inevitably draw on many patterns, whether consciously or otherwise, which suggests that in practice a lone pattern is something of a curiosity. The most obvious presentation of multiple patterns is in the form of a collection.

To date, the most ambitious collection of patterns we know of is Grady Booch's Handbook of Software Architecture [Booch]. This project aims to fulfill much of Bruce Anderson's original vision of an architecture handbook, which we outlined in Section 0.1, Beginnings… At the time of writing, the Handbook of Software Architecture ...