Introduction to Design Patterns
This chapter is from the book
This chapter is from the book
This chapter is from the book
Introduction To Patterns
This book is for developers who know Java and who have had some exposure to the book Design Patterns (Gamma et al. 1995). The premise of this book is that you want to
Deepen your understanding of the patterns that Design Patterns describes
Build confidence in your ability to recognize these patterns
Strengthen your ability to apply these patterns in your own Java programs
Why Patterns?
A pattern is a way of doing something, or a way of pursuing an intent. This idea applies to cooking, making fireworks, developing software, and to any other craft. In any craft that is mature or that is starting to mature, you can find common, effective methods for achieving aims and solving problems in various contexts. The community of people who practice a craft usually invent jargon that helps them talk about their craft. This jargon often refers to patterns, or standardized ways of achieving certain aims. Writers document these patterns, helping to standardize the jargon. Writers also ensure that the accumulated wisdom of a craft is available to future generations of practitioners.
Christopher Alexander was one of the first writers to encapsulate a craft's best practices by documenting its patterns. His work relates to architecture—of buildings, not software. A Pattern Language: Towns, Buildings, Construction (Alexander, Ishikawa, and Silverstein 1977) provides patterns for architecting successful buildings and towns. Alexander's writing is powerful and has influenced the software community, partially because of the way he looks at intent.
You might state the intent of architectural patterns as "to design buildings." But Alexander makes it clear that the intent of architectural patterns is to serve and to inspire the people who will occupy buildings and towns. Alexander's work showed that patterns are an excellent way to capture and to convey the wisdom of a craft. He also established that properly perceiving and documenting the intent of a craft is a critical, philosophical, and elusive challenge.
The software community has resonated with Alexander's approach and has created many books that document patterns of software development. These books record best practices for software process, software analysis, and high-level and class-level design. Table 1.1 lists books that record best practices in various aspects of software development. This list of books is not comprehensive, and new books appear every year. If you are choosing a book about patterns to read you should spend some time reading reviews of available books and try to select the book that will help you the most.