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Let's take a look at the context object here so we can see the product object with reference to the

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product state, which is the interface that will serve as a contract for the state implementation classes.

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We can see that inside the constructor we assign the first state as the available state, which is for

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sale.

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Right.

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This would be the first the initial state of of a product inside the store.

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And we also have the letters and the setters because we encapsulate this property in a private variable.

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Here we are.

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Of course, we have some methods for getting to the previous state or to the next state.

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And we also have a method to print the current state, which is the one that you see here, which will

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have a statement, a system out of control and statement which will display the current state of the

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product.

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Plus, this is the interface for for the states.

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So this will be the contract.

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We we have only two methods.

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The next and the previous.

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Both of them will take a product as an argument.

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So let's see the first state here, the available state, so you can see that the next method here will

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switch, will set the new state of the product, which will be the product from from its arguments to

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the solid state, which is the next one.

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So basically, we have two states, this one being the first and the solid state being the second.

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So the next method will switch the state to the next one to to the last state, basically.

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And the previous state won't do anything, will just output a system.

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Although the saying that the previous state, there is no previous state for this, this product, which

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is of course understandable, and the souled will have the same problem for the next because we don't

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have a next state and for the previous it will switch the previous state.

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It was the product to its previous state, which is the available state.

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So let's see how this works.

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So basically, reinitialize here a new product and we here put some system of different elements to.

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To bring some clarity to to this to this example, and here we switch the states to the next step,

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we print the new status and we also do another action that is supposed to bring the product to its previous

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state.

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And then we print the status again, the status, meaning the current state.

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So let's run this.

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So as you can see, when the smartphone has been sold, which is our product, the product that we use

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in our example, the status for the state will be equal to salt.

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But when the smartphone will be returned by the customer, the status will switch again to the available

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state.

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So as you can see, we do not make use of complex case statements or if else, statements.

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We just delegate the state of the product to a different class, to a different set of classes, actually,

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which will handle all the implementation for that state and all the actions that we need to do in that

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specific state for us.

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Right.

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So we won't need to to create here a lot of code, a lot of complexity, because this will eventually

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make the code unreadable and very, very hard to refactor.

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All right, so that's it for this party.

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Join me in the next tutorial where we are going to discuss about the strategy of putting.