L6: Making Software Manageable

Question 1

How to make software more manageable?

Answer 1

Separation of concerns / divide and conquer:
- Divide system into smaller units to reduce complexity and improve independence

Abstraction:
- Hide and generalise details to reduce complexity
- Level of abstraction / hiding differs during the design

Encapsulation, modularity, and information hiding:
- Place information into a unit and hiding it to prevent unwanted access
- Design units/modules with all relevant data and only expose it via an interface

Question 2

Coupling and cohesion

Answer 2

• Coupling: degree of interaction between units
• Cohesion: degree to which a unit fulfills one purpose

Question 3

Information Hiding

Answer 3

• Reveal as little information to the outside as needed
• Prevent data manipulation
• Ensure integrity of the unit
• Allows access via a single, controlled interface

Question 4

Problems with divide and conquer

Answer 4

• It can be challenging to define a good separation of concerns
• Needs experience and typically some experimenting
• Separation of concerns often leads to overhead
• Functions cannot be defined in isolation