USE CASES • • Contract between stakeholders about system behavior Captures: – Request from primary actor – System response – Implications for other stakeholders • • • To be agreed by non-technical users Usually in text form (also business processes, flow charts, programming languages) Used for different purposes – – – – • To To To To be the functional requirements for a system describe business processes form the basis for user documentation document the design of a system One size doesn’t fit all – Executives need business oriented use cases – Mission critical apps require unambiguous, thorough descriptions Buy Goods USE CASE 5 Goal in Context Buyer issues request directly to our company, expects goods shipped and to be billed. Scope & Level Company, Summary Preconditions Success End Condition We know Buyer, their address, etc. Buyer has goods, we have money for the goods. Failed End Condition We have not sent the goods, Buyer has not spent the money. 1a, 2a Actors Buyer, any agent (or computer) acting for customer. Credit card company, bank, shipping service Trigger purchase request comes in. DESCRIPTION Step Action 1 Buyer calls in with a purchase request 2 Company captures buyer’s name, address, requested goods, etc. 3 Company gives buyer information on goods, prices, delivery dates, etc. 4 Buyer signs for order. 5 6 Company creates order, ships order to buyer. Company ships invoice to buyer. 7 Buyers pays invoice. Step 3a Branching Action Company is out of one of the ordered items: 3a1. Renegotiate order. 4a Buyer pays directly with credit card: 4a1. Take payment by credit card (use case 44) 7a Buyer returns goods: 7a. Handle returned goods (use case 105) EXTENSIONS SUB-VARIATIONS Branching Action 1 Buyer may use phone in, fax in, use web order form, electronic interchange 7 Buyer may pay by cash or money order, check, credit card THE MIT VIEW OF THE FIRM ORGANIZATION’S VALUE PROPOSITION INFORMATION VALUE PROCESS VALUE MATERIAL VALUE ARCHITECTURE ORGANIZATION’S DEEP STRUCTURE OF BUSINESS PROCESSES COMPUTER ACTIVITIES DESIGN BUY MAKE HUMAN ACTIVITIES SELL MANAGE TECHNOLOGY MACHINES & MATERIALS PEOPLE ENVIRONMENT