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Objects make your code organized and easier to understand.

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Object oriented programming means organizing your code around objects.

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And the purpose of object oriented programming is to write high quality code.

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In this lesson, you will create two car objects.

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Before we start, create a new folder.

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Call it section seven.

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Inside the folder, create a file named Main Java, and then make sure that your class has a main method.

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So your boss wants you to write code based on these requirements.

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And before you write a single line, step one is to identify the objects.

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We can define what an object is based on two criterias.

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An object is a thing that contains fields.

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And furthermore, an object is a thing that performs tasks.

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Take some time to remember these two bullet points.

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Now then, how many objects can you identify from this passage?

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I only count one type of object car.

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So based on the first bullet point, which describes an object as a thing that contains fields, car

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is a thing that contains the fields make price year end color.

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Going back to our criteria, an object is also a thing that can perform tasks.

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In this case, a car object can drive.

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So let's keep track of our progress.

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We identified one object, a car.

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A car is defined by its make price year end color.

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And furthermore, a car can drive.

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So that was step one.

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You identified one type of object car.

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Step two is to create a class.

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The class is a blueprint from which you can create an object.

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Previously we identified that every car is defined by its make price year and color.

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So based on these fields, we can create a blueprint.

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Our class, our blueprint, will declare that every single car needs to define a make price year end

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color.

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Inside your project.

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Create a new file called Car Java.

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And inside the car class, we declare that every single car needs to define a make.

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It needs to define a price.

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A year.

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And a color.

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And that's all.

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The car class is a blueprint, and from this blueprint we can create many car objects.

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And that's actually step number three from the car class.

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You will create car objects.

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The object will be of type car.

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Here we are creating a new object of the class.

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The variable automatically stores a reference to that object.

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And once I create an object, I can modify its fields.

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So what we'll do when our code is from the car class, from the blueprint that we just developed, we're

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going to create two car objects.

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The first object will be if type car.

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I will call the variable Nissan, and the Nissan variable will store a reference to a brand new object

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of the car class.

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This car object is automatically going to contain four fields.

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We can set the first field the make equal to Nissan.

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We can set its price equal to $10,000.

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We can set it's year.

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Equal to 2020.

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And we can set its color.

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Be equal to green.

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Let's visualize the runtime.

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Here we are creating a new object of the car class and the variable Nissan stores a reference to that

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object.

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And the object is fields by default are going to start at zero or null.

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Here we update that object as make to Nissan.

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Here we update it's priced at $10,000.

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Here we update that object says year to 2020.

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And here we update this object as color to green.

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And how easy was that?

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Using the same blueprint, I can create another object of the car class.

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I will call this variable dodge.

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And the Dodge variable will store a reference to a brand new object of the car class.

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This brand new car object is going to have a make that equals dodge.

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It's going to have a price that equals 11,000.

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It's going to have a year.

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Of 2019.

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And it will have a color of blue.

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Before we visualize the runtime, there is a text file inside of your resources folder.

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Please take some time to download it.

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The file that you just downloaded contains code that prints the fields of each object.

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So copy it into your main class and let us once again visualize the runtime.

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Press debug.

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Here we are creating a new object of the class.

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This variable, Nissan automatically stores a reference to that object.

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The object is fields by default start zero or null.

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Here we update that object as make.

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Here we update its price.

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Here we update its year and here we update its color.

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Here we're creating another object of the car class, and the variable dodge is going to store a reference

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that points to that object.

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The object is fields by default, start at zero or null, and once again, we update every single field

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in that object.

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At this point, we successfully created two objects of the car class, and finally, we can print the

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fields of each object.

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The first object, if I hover over the variable that points to it you can see, has a make of Nissan

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a price of 10,000 a year of 2020 and a color of green.

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So that's what's going to print.

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Beautiful.

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The second object, if I hover on the variable that points to it, has a make of dodge, a color of

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blue, a price of 11,000 and a year of 2019.

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Let's just press continue.

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And that is exactly what Prince.

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So to recap, you created two objects of the car class.

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A car class is a blueprint from which you can create concrete car objects.