Structural Design Patterns in Modern C++ - Introduction to the Decorator Pattern

The video tutorial discusses the Open Closed Principle, highlighting the limitations of modifying existing code and the static nature of inheritance. It introduces the decorator pattern as a solution, allowing dynamic addition of behaviors to objects at runtime without modifying existing code. The tutorial explains the intent, structure, and implementation of the decorator pattern, emphasizing its flexibility and runtime capabilities. It also briefly compares the decorator pattern with the strategy pattern, noting their differences in altering object behavior.

What principle is violated when modifying existing code to add new features?

• Open Closed Principle

• Interface Segregation Principle

• Single Responsibility Principle

• Liskov Substitution Principle

What is a decorator also known as?

• Proxy

• Bridge

• Wrapper

• Adapter

What is a key advantage of the decorator pattern over inheritance?

• It enables dynamic addition of responsibilities.

• It reduces the need for interfaces.

• It allows for static behavior changes.

• It simplifies code structure.

How does the decorator pattern maintain the Open Closed Principle?

• By creating new classes for each feature.

• By adding features without altering the original component.

• By using inheritance to add features.

• By modifying the original component directly.

What is the role of the base class in the decorator pattern?

• To store data for decorators.

• To define the interface for decorators.

• To implement concrete functionality.

• To manage runtime behavior.

What is a potential alternative to the decorator pattern for changing an object's behavior?

• Observer Pattern

• Strategy Pattern

• Factory Pattern

• Singleton Pattern

Why should decorator classes be lightweight?

• To enable them to handle multiple responsibilities.

• To prevent them from becoming too heavy to use.

• To allow for easy modification of the base class.

• To ensure they can store large amounts of data.