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Let's start by looking at the machine interface here.

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So this is the component that we see in our diagram.

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It has only one function that one and only one method that will return the street to us.

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And here is the implementation of the machine.

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I decided to go it with colors because it's a good example for the decorator partner.

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You can decorate a car with several functionality, several several features.

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So it's easier to understand using this example.

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So we just invented this operation method and we only risky work car.

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You will see.

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You will see why.

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And on the other side, we have the decorator, the car decorator abstraction in the form of an abstract

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class which implements the same machine interface.

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We have a machine object here.

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This doesn't need to be encapsulated, meaning that it doesn't have to have private access modifier

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because you will need this object in the concrete decorator's that we will implement.

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And here we have the constructor.

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We will take a machine as an argument and we set the machine, the property of this decorator with this

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machine argument and the operation will return.

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What the machine wants to do, operation implementation of the machine will return.

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So this is very straightforward.

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This these are these two of the navigation and the parking assistant are the concrete decorators that

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we have.

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So as you can see, it extends the navigation, extends the car decorator class.

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The constructor is basically the call to the super method, the super constructor and the operation

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will return the result of the machine, the operation, but also plus navigation.

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So basically, we are adding a new feature to the to the car, which is to our base object.

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And the same applies for the parking system as well.

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So as you can see, the same code, but instead of adding navigation, we are the parking system and

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the class which contains our main method is looking like this.

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We basically create the new machine object with the following implementation.

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So basically we are adding all the decorators in order to create a car, which parking assistant and

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navigation.

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So this the system, although through the lens, should output what the machine looks like, what the

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what are the features that the machine has.

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So let's run this.

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So as you can see, we have the base class near the base object, which is a car, and we add the parking

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incident, the parking assistant and a navigation features to it.

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So basically, this is the stuff that's about it.

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This is how you create this is how you implement the decorator pattern in your code.

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It's always helpful to have this pattern whenever you want to decorate an object with additional additional

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stuff, additional features.

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Right.

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So in this way, you won't affect your base object.

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You won't affect the structure of the base object.

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But also you can add at the same time, you can add new functionalities, new features, and each class,

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each class that you add will be responsible of each feature.

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So it's actually very, very straightforward.

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But like I said in the previous video, the downside is that you will have a lot of classes.

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If you have a complex object, like a car, for example, you will have a lot of objects that a lot

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of classes that you you need to create for each feature because a car has a lot of features.

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So if you want to be granular about it, then you will have to add you have to transpose each feature

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of a car into a class which will increase the volume of your code.

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That's it about the decorator pattern.

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Join me in the next story of where we are going to discuss about the facade pattern.

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So, so and I story.