Object Oriented Design - Lecture 1: Introduction to SDLC

This post is the note of lecture 1 of the course "Object Oriented System Analysis and Design". Videos can be viewed at https://www.youtube.com/watch?v=ODeQ0rF59kI&index=3&list=PL6XklZATqYx9dj72MKG6wLYjljeB2odra.

Lecture 1

1. System Design Methodology

1. System Design Lifecycle (SDLC)


1. Identify the problem and obtain approval
2. Plan the project
3. Understand the details of the problem or need
4. Design the system components (Draw a diagram)
5. Build, test, and integrate system components
6. Deploy the system

2. Actual approaches used to develop a particular information system

1. Unified process
2. Extreme programming
3. Scrum (suitable for team work)
4. Agile development (emphasizes flexibility to anticipate new requirement during development)

3.RMO example to illustrate SDLC

1. Need/requirement
1. Small information system
2. Being added to large supply chain management system
3. Demonstrate one iteration of the small project, assuming there are more
2. Look through all six phases in SDLC
1. Phase 1: Identify the problem
• Problem: purchasing agents attend appareal and fabric trade show around the whold to order new products from supplier.
• Need: build a new information system (app) to track information about supplier and new products while at trade show.
2. Phase 2: Plan 
• System vision document (problem description + system capability + business benefits).
• Work breakdown structure (tasks, whose responsibility, estimated working hours)
3. Phase 3: Analysis (understand the details of the problem or need)
• Basic ideas:   supplier subsystem + product subsystem
• Use cases (一般包括增删查改) + a use case diagram:
    Supplier: look up suppliers; enter/update/delete supplier information; look up contact; enter/update/delete contact information, etc
    Product: look up product information; enter/update/delete product information; upload product image, etc
• Information diagram (for supplier/product, what information we should have)
  
4. Phase 4: Design
• Design databases: table design, key-index identification, attribute types, referential integrity
  
• Design the system's high level structure: 
• Browser, window, smart phone
  
  
• Architectural configuration (components)
• Class diagram
  
• Subsystem architecture
  
5. Phase 5: Implementation
6. Phase 6: Maintenance