Chapter 15. Catalog
Note
“Who's in charge here?”
This is a moderate-size example involving both refactoring and development. The goal is to demonstrate how we can use refactoring to explore design decisions and their consequences.
Introduction
Imagine a store selling a variety of items. During a brief design session, we decide there are several classes of interest: Item (something for sale), Catalog (the set of all items), and Query (to find a specific set of items).
Catalog and Query must collaborate to search, but how that collaboration will occur needs to be decided. Imagine a fourth class, Interrogator. It has a method evaluate(catalog, query) that returns a list of items. This method encapsulates the decision about how to handle things.
Get Refactoring Workbook now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.
