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The 18 pattern is best used whenever there's a need to traverse a data structure and access its elements.

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You may wonder why you would need this battery instead of a loop to traverse a collection.

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Well, the good thing about this battle is that it does not expose the underlying structure of the container

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that is being traversed.

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The iterators decouples the data from the algorithm used for traversing a container.

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A very good example of an iterator is the Java dot dot iterator interface from the Java API.

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Looking at the UML diagram for this pattern, you can see that we have two abstractions for the container

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that will be traversed and for the iterator, the employee director class will implement the container

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and it will be based on the list containing the names of the employees of a company.

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When they enter, their class will implement the iterator and it will contain the algorithm for its

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overseeing the employees container.

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Let's see how this can be implemented in the code.