Description:
When software developers mention design patterns, the chances are that
they are talking about Design Patterns, the classic book by the Gang of
Four, rather than design patterns in general. Even when they are
talking about the pattern concept, as opposed to specific patterns,
they often think in terms of the form and idea presented in GoF, and
rarely beyond.
Since the publication of the seminal work by the GoF in 1994, however,
a great deal of research and practice in patterns has led to a better
understanding of both the pattern concept and the strengths and
weaknesses of the GoF patterns themselves.
This tutorial revisits the GoF patterns, reflects on them, deconstructs
them and re-evaluates them from the practitioner's perspective: why
patterns such as Abstract Factory, Builder, Flyweight, Command and
others are missing vital ingredients to be proper parts of an
architectural vocabulary; why Singleton decreases a system's
flexibility and testability; why Iterator is not always the best
solution for traversing aggregates; why State is not the only state
pattern; why some patterns, such as Bridge, are more than one pattern;
and what you can do about it.
