Connie's Convenience Store - About Peter Coad

22 Connie’s Convenience Store Applying Patterns: Select and Organize Problem-Domain Objects
#4. “Place-Transaction” Pattern transaction patterns
number
name
address
aboutMe
Place
howMany
howMuch
rankTransactions
calcOverTransactions
ansOverTransactions
• Typical object interactions
howMany —> calcForMe calcOverTransactions —> calcForMe
howMuch —> calcForMe rankTransactions —> rateMe
• Examples
Place: airport, assembly-line, airport, bank, clinic, depot, garage, geographic entity,
hangar, hospital, manufacturing site, plant, region, sales outlet, service center,
shelf, station, store, warehouse, zone.
Transaction: agreement, assignment, authorization, contract, delivery, deposit,
incident, inquiry, order, payment, problem, report, purchase, refund, registration,
rental, reservation, sale, shift, shipment, subscription, time charge, title,
withdrawal.
• Combinations
participant-transaction; specific item–transaction; transaction–transaction line item;
transaction–subsequent transaction. Also, using “place” as a container: containercontent;
container–container line item.
Connect the players (Figure 1–12):
Store Sale
n 1
n 1
Figure 1–12: Store-sale.
Transaction
number
date
time
status
aboutMe
calcForMe
rateMe