Systems Analysis - Drawing a Use Case Diagram
Related learning outcomes from the unit outline:
- Demonstrate evidence of the knowledge set and skill set required by the systems analyst.
- Apply structured techniques to the analysis of current systems and modelling of future systems.
Background: Use Case diagrams are one of the four core UML diagrams. Use Case diagrams express the functions of a system in an abstract, readable way as well as specifying the actors involved in the use cases.
Tasks:
1. Split yourselves into groups of four. Read the following text and determine the requirements. List any assumptions you make.
2. Using pencil and paper draw a draft use case diagram of the system, using <> and <> stereotypes as appropriate.
3. Discuss your diagram with your tutor. Explain your assumptions. If you have time, gain practice with Visio by re-drawing your draft diagram in Visio. The software is provided to you free and can be found by searching the ECU website for MSDNAA (msdnaa.scss.ecu.edu.au).
The system to be developed is a GUI that allows a passenger to purchase a train ticket. Before boarding a train, a passenger must have a valid ticket. At the ticket machine, a potential passenger can select the number of zones s/he wishes to travel. The passenger can insert cash and/or coins to at least the value of the journey. The machine returns the ticket and any change, unless the ticket machine is out of change. A passenger can cancel a transaction at any time prior to a ticket being issued. If there is no passenger input after 30 seconds, the ticket machine cancels the transaction. If a ticket machine is out of order it will not accept input. A potential passenger can purchase a single journey ticket, a return ticket or a multi-rider ticket (which is an advance purchase of the equivalent of ten tickets for the same number of zones that carries a 10% discount).