Lecture 9: OOP (Advanced Topics)

Overview

This lecture covers advanced Object-Oriented Programming topics in C++, focusing on class relationships, polymorphism, resource management, and design principles that enable flexible, maintainable code.

Learning Objectives

By the end of this session, you will be able to:

• Understand class relationships: association, aggregation, composition, and inheritance

• Distinguish compile-time vs. runtime polymorphism and use virtual methods

• Apply override, = default, and final keywords correctly

• Choose between auto and explicit base types for polymorphic objects

• Implement virtual destructors to prevent resource leaks

• Create abstract classes with pure virtual methods and concrete implementations

Topics Covered

• Class Relationships
  • Association
  • Aggregation
  • Composition
  • Comparison: Aggregation vs Composition
  • Inheritance
  • Key Takeaways
• Polymorphism
  • Compile-Time Polymorphism
  • Runtime Polymorphism
  • When to Use auto vs. Explicit Base Type
  • The override Keyword
  • Avoid Slicing & Embrace Polymorphic Collections
  • Requirements for Runtime Polymorphism
• Destructors
  • Key Characteristics
  • What Does a Destructor Do?
  • Destructor Execution Order
  • virtual Destructors and Inheritance
  • The = default Keyword
  • Common Patterns
  • Common Pitfalls
  • Best Practices
• Abstraction
  • Key Benefits
  • When to Use Abstract Classes
  • How is Abstraction Implemented in C++?
  • Pure virtual Methods (= 0)
  • Concrete Classes
  • Design Patterns with Abstraction
  • Best Practices
  • Common Pitfalls
• The final Keyword
  • Purpose and Benefits
  • Prevent Class Inheritance
  • Prevent Method Overriding
  • Combining final and override
  • Design Considerations
  • Common Patterns
  • Best Practices
  • Common Mistakes
• References

Next Steps

• Lecture 10: Introduction to ROS (Robot Operating System)

• Apply OOP principles to robot software architecture

• Learn about ROS nodes, topics, and services

• Build modular, reusable robot components