Decorator Pattern
The Decorator Pattern is a structural design pattern in object-oriented programming that allows behavior to be added to individual objects dynamically, without affecting the behavior of other objects from the same class. It involves creating a set of decorator classes that wrap the original class, providing additional functionality while maintaining the same interface. This pattern is useful for extending functionality in a flexible and reusable way, often used to avoid subclass explosion.
Developers should learn the Decorator Pattern when they need to add responsibilities to objects at runtime without modifying existing code, such as in GUI toolkits, I/O streams, or middleware systems. It's particularly valuable in scenarios where multiple independent features might be combined, like adding logging, encryption, or compression to data streams, as it promotes the Open/Closed Principle by allowing extension without modification.