Datasheet

Understanding Design
Patterns
Usually when I pick up a book and see a chapter longer than five pages about a topic that I ’ m not
the most familiar with, I tend to get scared. More than five pages may see me dropping the book
and running away, flailing my arms and shouting about how tough these computers are! While
this chapter may be longer than five pages, don ’ t be discouraged. The term Design Pattern is just a
fancy name for something that is not all that complex. A good portion of this chapter is taking
what you may already know and use regularly and refining it to a more concise definition. So, let ’ s
jump in and see what Design Patterns really are.
What Are They?
The story of Steve that follows helps describe Design Patterns in a real - world context. I ’ m hoping
that you ’ re not too familiar with this story!
An All Too Common Example
Steve works at a large insurance firm. His most recent task was developing a way to show customer
information to the call center representatives over a web interface. He designed a complex system
that would allow the reps to search for a customer, enter call logs, update customer coverage
information, and process payments. The system went into place smoothly, minus the few bumps
and hiccups that a new installation in a production environment always runs into. Steve is happy,
relaxed, and ready to sit back in the break room sipping his free coffee.
Overnight, the insurance company triples in size from its most recent investment. Not only is Steve
called back to work on providing new scalability and enhancements to the call center software but
there has also been buzz about adding some new features to the corporate site to support the new
acquisition ’ s customers. Steve ’ s department is also increased to include two new developers, Andy
and Jason.
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