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The solution is going to cover part for.

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We'll come back to the third test case, but the fourth one tells us to check if a movie is unavailable

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after it's rented.

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So I'll write a unit test named Rent a movie test.

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And inside our rent out The Godfather.

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And then our unit test is going to assert The Godfather isn't available after Rentoul assert false store,

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get movie.

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At index one is available.

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OK, now inside, start our Java write code to make the test failed.

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I'll define a function named Arunta movie.

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It's a void and receives a string parameter name.

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And for now, we'll do nothing.

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Our test fails, that's fine, let's write code to make it pass.

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Inside the movie, I'm going to create a loop that runs through the size of the array list.

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And when it finds a name that matches the one being Pastan.

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Then we'll set its availability to false.

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If we were on our test now, it should work.

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I can run the debugger.

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Rent, movie updates, the availability to false and our assertion passes.

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Now, can rent movies be simpler?

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Absolutely.

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Rent movies, doing way too much work, it's retrieving the index and it's setting the movie's availability

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to false.

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It should only be performing a single task.

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So we'll create another method that's solely responsible for retrieving the movie index, a function

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name is get movie index.

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It returns an integer and receives a string parameter called name.

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And inside this function, we're going to copy over the logic from rent a movie.

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And if it doesn't find a movie, we still need to return and we'll use negative a thousand to indicate

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that it couldn't find anything.

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OK, and now we can all get moving index from rent a movie.

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And this looks better, I like it when each function is only performing one task.

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This is what I mean when I say Modula.

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OK, if we rerun the test, it passes good, we don't have any bugs.

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But we still have to ask the question, can we refactor?

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And the answer is yes, loops are pretty messy.

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And since Java eight, we can use something called an end stream.

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What an end stream does is it goes through a pipeline of functions until it returns an integer that

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represents an index.

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First, you need to specify the range from which you're getting the index.

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The range is going to start from zero until the size of the array list.

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The next operation is filter.

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Filter, expecta, lambda expression that returns a boolean, the lambda receives each index from zero

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until the size of the array list.

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We're going to call it I.

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And for each index, we're going to return a boolean that checks if the name of the movie object at

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the requested index.

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Equals the parameter.

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And Stream is going to filter the index for which this condition is true.

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And now we need to return this index, so we'll use the terminal operation, find first, find first

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is a terminal operation because it ends the pipeline by returning the first index for which this condition

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is true.

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And if fine first, does it find anything if all of the indexes return false?

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Then we'll say or else.

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Negative, a thousand.

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And we'll return the result that comes out of this pipeline.

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OK, as you can tell by now, I'm a pretty big fan of replacing Lupe's with a pipeline of functions

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whenever I can.

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And as always, as you refactor, run the unit test to make sure there aren't bugs and there aren't

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any perfect.

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So now we ask ourselves the same question, can it be a refactored and the answer is yes.

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If your expression is only a single line, then you can remove the curly brackets as well as the return

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keyword.

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And Java is going to know you intend on returning the Boolean.

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We run the unit test.

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And beautiful.

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Once again, can the code be refactored?

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Nope, we're done.