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A top class can use the constructor of its parent class.

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The child class uses its constructor to update its fields.

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The child class uses the parent constructor to update inherited fields.

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In this lesson, each child, the class will call the parent constructor.

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Super refers to the super class, which also means parent class.

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Now, super with brackets refers to the constructor of the super class, the constructor of the parent

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class.

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If you want to call the constructor of a parent class, use super.

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An inside in the parameters that the constructor expects.

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Now, let's say our parent class, as of the following instructor, then this is how you would call

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the parent constructor pretty cool.

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Now, inside, man, we have two objects, put a break point and run the debugger.

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Creates a new object of the short class.

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OK.

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The child constructor receives four parameters.

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But it only updates one of them, the rest of them remain zero or no.

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Now, it's impossible to update inherited fields from the child constructor, the child class needs

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to use the parent constructor.

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So inside product Java, critic, instructor, public product.

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That receives three parameters, double price, string color, string, brand.

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And update each field in the current object with a parameter, the stock price equals price, this color

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equals color.

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This brand equals brand.

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OK, and now the child class needs to use the parent's constructor to update the fields that it inherits.

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You can refer to the superclass, the parent class using super.

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And you can refer to the super classes constructor by adding Brackett's.

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And inside, you can add three of the parameters into the super constructor.

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Now, the pants class also needs to use the parents constructor to update the fields that it inherits.

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And that's it now we get to run the debugger.

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It creates a new object of the short class.

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The constructor receives four parameters.

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It passes three of them into the parent constructor.

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The parent constructor updates three fields in the current object that's being created, and once the

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parent constructor is done, the child, the class uses its constructor to update its field.

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OK, moving on to the object.

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It creates a new object of the pants class, the constructor receives four parameters, three of them

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are passed into the parent constructor.

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The parent constructor updates three fields in the current object that's being created.

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And once the parent constructor is done.

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The child class is using its constructor to update its field.

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All right, let's go back to the subject of polymorphism inheritance allows an object to take many forms.

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In other words, inheritance allows an object to be polymorphic.

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Our shirt to class inherits from the product class so we can declare this as type products, our pants

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class also inherits from the product class so we can also declare it as type products.

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Now, you might be wondering, why is polymorphism useful?

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The answer to that is flexibility.

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Here we create an object of the class, and here we created an object of the pants class, but they're

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both of type product.

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So we can store them inside the same array.

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I can create an array of type product products is equal to a new array that can store product objects.

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And here I can put the shirt.

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And the pants.

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Although this is a shirt object and this is a pants object, each one is taking the form of a product

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object.

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This is polymorphism.

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A class can take its own form or it can take the form of the class it's inheriting from.

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A child class can use the constructor of its parent class.

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The child class uses its constructor to update its fields.

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And the child class uses the parent constructor to update inherited fields.

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Now, super with brackets refers to the constructor of the super class, the constructor of the parent

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class.

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If you want to call the constructor of a parent class, you super.

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And inside Passan, the parameters that the constructor expects.