The Decorator pattern

- [Instructor] The Decorator Pattern … is one of those patterns of composition … that you either get or you don't … but once you get it, its power becomes so great … that you use it often within your development techniques. … Within the Spring framework, … decorators are used all over the place. … The frameworks uses decorators … to do much of its operations. … Injecting your decorated objects, … however, is difficult in Spring … because of how bean references work … specifically around shared interfaces. … In order for you to use the decorators for your beans, … you have to use Qualifier annotations … which then makes your code less about IOC … and more about you controlling the injection … throughout your application. … Now, the pattern and the way that it works in a nutshell … is pretty straightforward. … You add responsibilities to an object dynamically … at runtime and you do so through composition … instead of inheritance. … Inherited base classes compose new behavior … and responsibility by becoming additive …