It defines an object that encapsulates how a set of objects interact. Mediator promotes loose coupling by keeping objects from referring to each other explicitly, and it lets you vary their interaction independently
- Decouples colleagues
- Simplifies object protocols
- Centralizes control
When to use:
- A set of objects communicate in well-defined but complex ways.
- You want to customize a behavior that’s distributed between several objects without using subclasses.