CS446 Study Guide - Final Guide: Liskov Substitution Principle, Evolvability, Observer Pattern

• School: University of Waterloo
• Department: Computer Science
• Course: CS446
• Professor: Mei Nagappan

Document Summary

Ood methods emphasize design notations: but these notations must be expressible in code. The importance of experience in ood cannot be overemphasized. Design-level reuse is valuable: matches problems to design experience, avoid previously-encountered difficulties. Good design can be marred by poor implementation, but good implementation cannot. Oo systems exploit recurring design structures that promote: abstration/flexibility/modularity/elegance. Capturing, communicating, and applying this knowledge is problematic. Must contend with similar constraints as architecture (e. g. , complexity, conformity, changeability, invisibility) The removal of detail while retaining essential properties of its structure. Plays a central role in the design process: enables the designer to focus on the key issues without being distracted by implementation. It can be easy for developers to be distracted by implementation minutiae. Different abstractions are appropriate for different applications and needs. System designs balance a variety of concerns. Design principles provide a set of considerations to keep in mind when modelling various dependencies in a design.