RSI - A Structured Approach Use Cases and HCI Design

The RSI Approach To HCI Design / Use Case Analysis Page 2 of 42
Table of Contents
ABSTRACT..........................................................................................................................................................................4
1. INTRODUCTION......................................................................................................................................................5
1.1. USE CASE ANALYSIS - IVOR JACOBSON ..................................................................................................................5
1.2. GOAL ORIENTED USE CASE ANALYSIS - ALISTAIR COCKBURN .................................................................................6
1.3. UML 1.3 «INCLUDES», «EXTENDS» AND SPECIALISATION ......................................................................................7
1.4. DESIGN BY CONTRACT - BERTRAND MEYER...........................................................................................................8
1.5. LEVELS OF ABSTRACTION IN OBJECT MODELLING - COOK AND DANIELS..................................................................9
1.6. HUMAN COMPUTER INTERFACE VIEW - VAN HARMELEN .........................................................................................9
2. MOTIVATION FOR THE RSI APPROACH......................................................................................................... 10
2.1. EXPERIENCES AS TRAINERS AND MENTORS AT RATIO ........................................................................................... 10
2.2. USE CASES IN PRACTICE ...................................................................................................................................... 10
Driver : Enter Parkade (Car Park) with Ticket........................................................................................................... 11
Success End Condition............................................................................................................................................... 11
Failure End Condition ............................................................................................................................................... 11
Primary Success Scenario .......................................................................................................................................... 12
Exceptions and Recovery Steps................................................................................................................................... 12
3. THE RSI APPROACH.............................................................................................................................................. 14
3.1. OBJECTIVES........................................................................................................................................................ 14
3.2. CLASSIFICATION OF LEVELS OF GRANULARITY AND ABSTRACTION........................................................................ 14
3.2.1. Requirement Use Cases ................................................................................................................................. 14
3.2.2. Interface Use Cases....................................................................................................................................... 15
3.2.3. Service Use Cases.......................................................................................................................................... 16
3.3. INTER-RELATIONSHIPS BETWEEN THE MODELS ..................................................................................................... 17
4. THE RSI PROCESS.................................................................................................................................................. 19
4.1. PROCESS OVERVIEW............................................................................................................................................ 19
4.2. INCREMENTAL AND ITERATIVE DEVELOPMENT ..................................................................................................... 19
4.2.1. Iterating ........................................................................................................................................................ 19
4.2.2. Increments..................................................................................................................................................... 20
4.3. DEVELOPING THE REQUIREMENT USE CASE MODEL............................................................................................... 20
4.3.1. Inputs:........................................................................................................................................................... 21
4.3.2. Outputs: ........................................................................................................................................................ 21
4.3.3. Sub-process:.................................................................................................................................................. 21
4.3.4. Example - hotel reservation system - requirement use case model................................................................... 21
4.4. DEVELOPING THE INTERFACE USE CASE MODEL.................................................................................................... 24
4.4.1. Inputs:........................................................................................................................................................... 24
4.4.2. Outputs: ........................................................................................................................................................ 24
4.4.3. Sub-process:.................................................................................................................................................. 24
4.4.4. Example (continued) - hotel reservation system - interface use case model ..................................................... 25
interface model use case summary diagram................................................................................................................ 25
4.5. DEVELOPING THE SERVICE USE CASE MODEL........................................................................................................ 29
4.5.1. Inputs:........................................................................................................................................................... 29
4.5.2. Outputs: ........................................................................................................................................................ 29
4.5.3. Sub-process:.................................................................................................................................................. 29
W5a - RSI LONG PAPER [42 PAGES].doc( Rev: 5) - 03/09/00