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Showing posts with the label Decorator Pattern

Wanna Cache? Decorate!!

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The Decorator Pattern Class Diagram: Decorator Pattern is one of the most powerful Design Patterns, and its important to understand why. It allows you to add functionality to a Class without changing it. You use delegation instead of inheritance by just wrapping the existing Class in a "Suite" of your choice while the Interface stays the same. This way, you can even wrap a Class into multiple layers of Decorators where every Layer has its own and different purpose, and the Original Class even stays the same. Other than that the Layers are completely interchangeable and removable, because they all have the same Interface. You can use your naked Object in the same manner as a decorated one with multiple Layers, and the rest of the Application wont even notice. Other components dont need to know whether a Class is decorated or not, because the only thing they care about is the Interface. The following Graphic should clear things up: Just follow the Steps: In the first example th...