Chapter 2 Problem 7
Entity-activity tableEvent Diagram
Use Case DiagramActivity Table
Domain Class Diagram
Mock Test
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Q1: Draw an Entity-Activity Table
Steps to follow: Put each sentence on a new line Number the sentences Highlight the “actor” and the related “activity”. It
is very important to connect the right actor with it’s activity
Set up the table Rather include ‘more’ information than ‘less’ We will eliminate some processes later to arrive at
the final table
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Entity-Activity Table: (Complete?)
Entity Line Nr Activity
purchasing department 1 purchase requests from other dept’s
customers 2 initiate the original purchase request
case worker 3 receives the request
case worker 3 monitors request
Case workers 4 process requests < R 1 500
Case workers 4 write a purchase order
Case workers 4 send it to the approved vendor
Case workers Supplier
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Send for bidding, request >= R1 500Sends bids
Case worker 6 Selects one bid
Case worker 6 Place order with vendor
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Problem/Solution Space:
Problem Space: Processes that are required to describe the
problem, but are NOT required to describe the solution.
Solution Space: Identifying processes that are required both to
describe the problem, and to develop a solution
Ref: The New Software Engineering, by S Conger, 1994, page 469
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Problem Space:
Line Nr 1: “The purchasing department receives requests
from other departments”: This is a problem description. Doesn’t say much about the “how”: the next three lines describe the “how”, being spesific.
Sort of introduces us to what they like to automate Line Nr 3:
“Monitor the request”: Our system will monitor it. That is our objective. Very vague statement
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Solution Space:
What is the problem, and HOW are we solving it: (What is the essence?) The purchase dept receives a request, transform
it to an PO, placed with some suppliers. It also fundamental to understand WHAT are
we automating It is a good idea to make some assumptions
at this stage
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Problem Domain:
Is the specific area of the user’s business that is included within the scope of the new system.
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Assumptions:
We are NOT automating the bidding process This will give a supplier access to our system
jeopardizing product prices, and our relationships with other suppliers
Such a decision must be taken at the strategic management level.
Ref: “Inter-organization SCMS”, pages111-115, Management Information Systems, by Oz and Jones (2008)
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Entity-Activity Table:
Entity Line Nr Activity
purchasing department 1 purchase requests from other dept’s
customers 2 initiate the original purchase request
case worker 3 receives the request
case worker 3 monitors request
Case workers 4 process requests < R 1 500
Case workers 4 write a purchase order
Case workers 4 send it to the approved vendor
Case workers Supplier
56
Send for bidding, request >= R1 500Sends bids
Case worker 6 Selects one bid
Case worker 6 Place order with vendor
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Activity Diagram:
Some scholars will draw the activity diagram at this point.
We will analyze the business processes more for a deeper understanding.
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Q2: Draw an Event Table
Steps: Identify all events: external, state, and temporal An event is something or an occurrence that
occurs at a specific time and place, can be precisely identified, and must be remembered by the system
Complete the table.
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Event Table:Event Trigger Source Use Case Response Destination
Customer wants to place a request to order
Request Inquiry
Customer Place a request
Request Information
Customer
Case worker places an order
New Order Case Worker
Place an Order
Order Details
Case worker; Supplier
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Q3: Use Case Diagram
What does the system do when the event occurs?
Use case is important to define functional requirements
The diagram is high level of abstraction: modeling the business logic. Platform, or technical Independent
Check out the next slide: Open for discussion!
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Points to take notice of:
<<includes>> or <<uses>> The included use case always occurs whenever
the use case which it includes <<extends>>
Augments the behavior of the use case which it extends
Explain the next slide!
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Explanation:
The use case Provide Exam Results may <<extend>> the use case Provide Enrollment
The former does not always extend the latter use case: new students do not yet have exam results
The <<includes>> always signifies that the former use case includes the latter. Before a study program can be entered, it must be a valid program of study.
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Q4: Activity DiagramIn-house Customer Purchasing Department Vendor
H
Make purchaserequest
Receiverequests
<1500?
Write purchaseorder
Request bid
Develop bid
Select bid
Send out bid
H
YesNo
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Q5: Develop a class domain model
At this stage you must have a pretty good idea what you are modeling …..
Identify classes: Analyze all the above descriptions and apply the Noun technique classes + attributes Identify relationships Make sure the above “describe the business rules”
of the proposed system