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The vehicle part interface will have only one method, which will accept an object of the type vehicle

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park visitor.

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Let's take a look at the second interface, which is the vehicle park visitor, which has also only

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one method, which is central to the visitor pattern, because using this method, you will be able

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to modify the behavior of the element class, which is in our case, which is the implementation of

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the vehicle part interface.

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So the vehicle parts basically allow let's take a look at the parts that are implementing the vehicle

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park interface so you can see the implementation of the equipment and for the car by the end.

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This is actually the same implementation for all the classes, for all the classes that are implementing

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this vehicle, the interface.

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And you can see that inside we use the object vehicle park visitor, which we handle as a parameter

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of this method here, and we call the visit method.

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And we also supply this object to to this to this method.

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Let's take a look at the implementation for the visitor interface.

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So we have only one class, as I said, but we can have multiple, depending on how many algorithms

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we want to apply to perform on on the element classes, which are the vehicle parts classes.

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And here we are just doing a system of Quintel and we are displaying the the vehicle part that is visited

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basically by displaying it's the name of the the name of each class.

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Let's take a look at the main method here.

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And we can see that we instantiate a new vehicle using those vehicles.

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And by the way, I haven't touched upon the vehicle class.

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This is pretty important, basically.

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So we have here an array of vehicle parts because this is what the vehicle is, right?

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It's it's a collection of of elements of of components.

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When put together, they assemble a vehicle.

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And here in the constructor we can see that we instantiate the vehicle.

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And also we we store all the components that are available in our vehicle.

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Part array here.

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The accept method for this one will we'll just iterate through the vehicle part array and we'll accept

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each vehicle part and then will supply this vehicle park visitor, which is sent to this method as a

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parameter.

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And here, of course, we call the visit method using this this object here.

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And let's get back to our class here.

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So we instantiate a new vehicle.

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So basically we are creating a new vehicle that is form of these three parts that we see here.

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And we call the excitement that this is what it takes.

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And of course, we instantiate a new vehicle, part show visitor, which is our algorithm that is applied,

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that is performed on this on this vehicle element object.

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And as you may have guessed, this should output the names of the components that are inside this vehicle

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that will use to assemble these vehicles.

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So let's see this in action.

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So as you can see, when we execute it, we just see here the implementation of this visit method that

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is inside the show visiter class, which will display in the console each name the names of each component

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that are forming this this vehicle class.

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All right.

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I know this can be a bit complex, but actually it's a pretty, pretty easy concept.

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It's not a very used you'll not encounter this pattern very often in in any code base, but it's a it's

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going to be a useful tool whenever you want to modify the behavior of an object at runtime, whenever

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you want to supply a new algorithm for your object, for actions and so on and so forth.

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All right.

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Thank you for watching the series.

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This was the last story of the design pattern series.

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I will be creating other other series as well.

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My plan is to create one for creating an application, a mobile application using ANGULAR with Ionic

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framework.

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So I will start working on that.

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And if you liked those videos, if you find them useful and I hope you.

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Please leave me a rating, please leave some feedback so that I can improve for the next videos.

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Thanks again for watching this and see you in the next series.