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Child classes can inherit from a parent class.

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In this lesson, two classes will inherit from a parent class.

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First, open up the folder for this lesson by following this path in your course resources.

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And now from the requirements, we can identify what seems to be three objects, store shirt and pants.

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We're not going to criticize or object and we're not going to be writing any unit tests just to keep

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the focus on inheritance.

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OK, let's get right to it, so first we have to create a shirt class.

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The requirements tell us that shirt has Fairfield's private string size.

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Private double price.

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Private string color.

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And private string brend.

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And naturally, we would create a constructor that receives four parameters.

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OK, now you want to set every field in the object that's being created equal to a parameter this size,

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equal size, the stock price equals price, the stock color.

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Equals color.

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This thought brand equals brand.

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For now, don't do anything else for this class.

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We'll move on and create a pince class.

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Public class pant's.

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And instead of a size field, the pants class defines a waste field.

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The remaining fields are identical to the ones for shirt, so could we just copy them over?

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You know how I feel about copying and pasting code.

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You should never do it before.

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Now I'll entertain it.

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Let's go through with it.

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And I guess we could also copy and paste the constructor.

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Change shirt, the pants, and instead of shrink size put into waist.

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Now, on that very same note, never, ever copy and paste code.

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If you copy and paste code, that means you're doing something wrong.

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What we did here is really, really bad.

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If you decide to copy and paste now, then you would end up copying and pasting together as the setters.

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Let me generate them really quick.

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And then, heck, why not copy and paste those as well?

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OK, now I hope you see my point, never copy and paste code, it's really, really bad practice.

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This is why inheritance is so important.

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Inheritance makes code reuseable shirt and pants need to inherit from a parent class.

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Shirt and pants share similar fields.

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Instead of defining the same fields in each class, they should inherit common fields from a parent

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class.

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In other words, shirt and pants are children of the product class inside models create a product class

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product Java.

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The product class is going to define fields that shirt and pants have in common.

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It's a private double price.

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Privates Tranquila.

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Private string brand.

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And now you can remove these fields from Pentz.

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We'll get errors here, so remove the field updates inside the constructor and delete all the letters

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and setters.

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We'll do the same thing for shirt.

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Remove the field updates in the constructor.

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As well as the getters and setters.

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Now, a class that extends another class inherits from its.

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Pants and shirt must extend the product class.

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And that's really it now the pants class and shirt class are inheriting from their parent class product.

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OK, now how can we make sure that pants and shirt are actually inheriting from the product class easy

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inside main an object of the shirt class.

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Percent a size of small.

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A price of five ninety nine.

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A color of blue.

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And a brand of will say job over time.

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Now, put a break point.

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And run the debugger.

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It creates a new object of the class, you can see the object includes the field inside the child.

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Class size.

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But wait a second, it also includes the fields that an inherited price color and bred.

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Let's make sure Pence is inheriting from product create a new object of the pants class.

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Passing a waste of 30 to a price of twenty four point ninety nine, a color of blue.

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And a brand of, let's say, Javor Klein.

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Run the debugger.

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It creates a new object of the pants class.

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You can see that the object includes the field inside the child class waste.

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But wait, it also includes the fields that an inherited price, color and bread, that is inheritance.

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All I want you to take away from this lesson is this when two classes share common fields, never defined

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the same fields in each class.

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Instead, each class should inherit common fields from a parent class.

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Child classes can inherit from a parent class.

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When two classes share common fields, never defined the same fields in each class.

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Instead, they should inherit common fields from a parent class.

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Shirt and pants shared similar fields, but instead of defining the same fields in each class, they

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inherited common fields from a parent class.