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Let's start by having a look at the originator class so we have the state stored as a string and we

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have a getter and a setter for the state's property, but also we have the methods for storing the state

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in the momentum class.

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So as you can see, we have this stored state mental method that will return a new memento and the memento

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will receive the state in the constructor to to save it in its in its properties.

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So we also have a retrieved state from Memento where we get the memento as a parameter.

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And as you can see, we call to get state to get there for the state property from the memento itself.

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So let's take a look then at the memento.

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So as you can see, we have the same property here called State.

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We have the constructor which initializes the state as well, and also to get the get state method,

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which will return the current state of of the object.

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Of course, we have the caretaker of the caretaker will will store a list of mementos here.

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All the mementos will will store a different state.

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So as you can see, these are the letters for adding for getting a memento, for retrieving it.

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Right.

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And also for the forgetting the size of the memento list, which is important for us to in order to

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navigate through all of the states that were created previously.

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So let's take a look then in the class in the main method here.

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So as you can see, we create an originator, we create a caretaker as well.

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We set some states to the originator.

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We also need to make sure that the caretaker also has those states stored as well, because otherwise

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those those states will be lost, will not be stored anywhere as soon as the state will be changed in

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the originator.

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So you need to make sure that you have this you call this method here as well.

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So we we switch to different states here.

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As you can see, there are only only four states.

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And also we do assist out with the current state of the originator just to make sure that the current

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state is the right one, which should be should be for in our case.

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And also we do a follow up and we retrieve all the states that were saved in the caretaker.

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So you will see that all the states here in our case will be will be saved.

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So everything will be retrieved and everything will be printed out in in the council due to this statement

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here.

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So let's see this in action.

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So as you can see, the current status for which is correct, because the last one was was the fourth

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state and we have three states because the fourth one wasn't added in the caretaker because it's the

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current one.

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We don't need to store the current one.

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So, as you can see, all the three previous states were were saved and retrieved by our method from

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the caretaker.

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All right.

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So this is it for this tutorial.

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Join me in the next one where we are going to discuss about the observer pattern.