Additional Notes
What problem does the Decorator pattern solve that subclassing cannot?
Track: Java
Topic: Design Patterns
Focus: Decorator Pattern
Java: Decorator Pattern
Answer
It prevents subclass proliferation by composing behaviors.
Subclassing can lead to a combinatorial explosion of classes when you need multiple combinations of behaviors. The Decorator pattern allows you to compose behaviors at runtime by stacking decorators, reducing the need for numerous subclasses. For instance, instead of having separate subclasses for each combination of shipping and packaging options, decorators can be layered dynamically.
Subclassing can lead to a combinatorial explosion of classes when you need multiple combinations of behaviors. The Decorator pattern allows you to compose behaviors at runtime by stacking decorators, reducing the need for numerous subclasses. For instance, instead of having separate subclasses for each combination of shipping and packaging options, decorators can be layered dynamically.
Topics: Decorator Pattern Design Patterns Java