|Type :||St (Structural)|
|Intent :||Attach additional responsibilities to an object dynamically. Decorators provide a flexible alternative to subclassing for extending functionality.|
|Applicability :||Use Decorator :
- to add responsibilities to individual objects dynamically and transparently, that is, without affecting other objects.
- for responsibilities that can be withdrawn.
- when extension by subclassing is impractical. Sometimes a large number of independent extensions are possible and would produce an explosion of subclasses to support every combination. Or a class definition may be hidden or otherwise unavailable for subclassing.