The document discusses characteristics of code quality including defining what code quality is, metrics to measure code quality, and practices and principles to improve code quality. Specifically, it notes that quality code is easy to understand, simple to maintain, easy to extend, can be reused in the future, and has unit tests. It also discusses why code quality is important by explaining how the cost of changing code rises over time and how poor quality can reduce productivity. Common code quality metrics and guidelines for functions and classes are also outlined.

1. Characteristics of code
quality

3. Code Quality
• What is code quality
• Code quality Metrics
• How to improve code quality
– Practices
– Design Principles
– Tools

4. CodeQuality
Quality code is
• Easy to understand
• Simple to maintain
• Easy to extend
• Reuse in the future
• Code must have unit test

5. Why we need to bother for code quality ?

6. Cost of change
• One of the universal assumption of software engineering is that cost
of changing a program rises exponentially over time .

7. Cost of change

8. Reduce Productivity

9. Code Quality Metrics
• Lines of code
• Depth of Inheritance Tree
• Coupling Between Object Classes
• Lack of Cohesion in Methods
• Maintainability Index

10. Lines Of Code
• Function
• Classes

11. Function
• Function should be small
• Functions should not have too many arguments
• Avoid flag arguments
• Command query separation
• Should follow SRP and OCP

12. Classes
• A class is a collection of data and routines that share a cohesive, well-
defined responsibility.
• A class might also be a collection of routines that provides a cohesive
set of services even if no common data is involved.