Connie's Convenience Store - About Peter Coad

Selecting Problem-Domain Objects Connie’s Convenience Store 11
About class names:
#38. “Use the Domain Vocabulary” Strategy selecting objects (names)
• Use the domain vocabulary.
• Encourage domain experts to eliminate names of things that aren’t their own.
• Don’t put words in your domain expert’s mouth.
• Don’t change the vocabulary unless the domain expert feels the need to do so.
• Don’t change the domain vocabulary—unless your domain experts choose to change
their own vocabulary.
About the class-with-objects symbol: the bold inner-rounded rectangle represents a
class; the outer-rounded rectangle represents one or more objects in a class. The class
name goes in the top section; attributes go in the middle; services go in the bottom.
Select places
#15. “Select Places” Strategy selecting objects (pattern players)
• Look for places where things come to rest, places that contain other objects.
• Examples: airport, assembly-line, bank, clinic, depot, garage, geographic entity, hangar,
hospital, manufacturing site, plant, region, sales outlet, service center, shelf, station,
store, warehouse, zone.
What places are important?
Here’s what to look for. Look for places where things come to rest. And look for
places that hold or contain other objects.
At Connie’s, that sounds a lot like:
– store
– shelf.
Both of these classes are in the problem domain. So far, so good.
#42. “System Responsibility” Strategy selecting objects (consider and challenge)
• Is the object something that your system is responsible to know or do anything about?
• If not, put it in the “not this time” model component.