To facilitate understanding of paper copies of this document, the appendix describes summarizes the patterns from [Coplien95] [Gamma+94] and [Beck] referenced in this paper.
This particular structure is based on that of the X-ray Timing Explorer project (XTE), currently in progress at the MIT Center for Space Research.
It can be argued that minimizing coupling is an important consideration in building any system, but because of the degree of decentralization and non locality in the projects being discussed here, it is especially important.
5Query Objects addresses the problem of handling the generation and executation of SQL statements in an object-oriented way, when you are trying to use a relational database to store objects.
6This pattern is not yet written, but would specify a mechanism for notifying a base class factory that a derived class factory has been created. The basic idea would be similar to the View/Model connection in a Model/View/Controller mechanism, but would also address issues of uniqueness (only one instance of each derived class can notify a base class) and guaranteed notification (the construction of any object/factory of the derived classes would generate a registration event automatically).
7Adapted from PLoP 94 paper. See [Berczuk95] for details.