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In this video, we are going to talk about the decorated pattern, which has the scope to add new functionality

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to an object without affecting its structure.

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This pattern creates a decorator class, which wraps the original class and provides additional functional

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beekeeping class method signature untouched.

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The decorator adheres to the single responsibility principle, which states that each object should

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have the responsibility of a single part of the functionality of a software.

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In other words, a class should do only one thing and two well.

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To achieve this decorator's use of principles like inheritance and composition.

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Let's a look at the following diagram.

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The component class is usually the abstraction, which can be either an interface or an abstract class.

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This class is implemented by the concrete component.

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As you may have guessed, the concrete component will be decorated.

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The decorating class will be inheriting the same component interface in order to make it similar to

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the concrete object that is being decorated.

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Below, we can have multiple complete decorator's for the same object.

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One of the weaknesses of this pattern can be the fact that a new class will be required by each new

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feature, which will increase the volume of the code.

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Let's have a look on how all this looks in code.