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What if I told you that almost everything in Java is an object, I'm going to circle back to the statement

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because it's pretty bold.

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First, you need to learn the difference between primitive versus class types.

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Primitive types are the most basic types of data.

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Int double boolean car.

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A variable of the primitive type stores, a value directly.

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Remember, this primitives represent a value, nothing more like the boolean true, or the number six

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primitives cannot be No.

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They have no methods.

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Class types, also known as reference types, are classes that you can create objects from.

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Dealership and car were class types from which we created dealership and car objects.

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Remember this, a class type variable points to an object.

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It can be no.

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And it can call methods from middle class.

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Here's a table that summarizes primitive versus class types.

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It's in your cheat sheet.

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Now, here's a fun fact for you, string is a class type.

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First, ask yourself why String capitalized because string is actually a class and class names, as

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you know, start with a capital letter Kemel case.

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So according to our table string variables, should story reference that points to an object.

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And guess what they do?

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When you define a string variable, you're actually creating an object of the string class, the variable

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stories, a reference that points to a string object.

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And it follows that when you said a string variable equal to another, it copies the reference inside

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both variables share a reference to the same string object.

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Wait a second.

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Shouldn't we worry about the reference trap?

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Nope.

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When you assign the variable and you string, it equals a brand new string object.

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In other words, the reference trap doesn't apply, so you don't have to worry.

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Back to our table, string variables can be know there are many methods we can call from the string

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class.

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Try calling them yourself from a random string and see what they do.

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Skinner is also a class type that you've seen many times.

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So according to our table Skinner variables should story reference that points to an object they do

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when you define a scanner variable, you're creating a new object of the scanner class.

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The scanner variable can indeed be no.

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And there are many methods we can call from the scanner class.

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In fact, we've been using them all along, like next int next, double next, long, next and next

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line.

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These are all methods that are defined in the scanner class, which you can call from your scanner object.

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Let's talk about the null value I mentioned earlier that primitive variables cannot be null.

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Variables, objects can be no.

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No, only applies when memory size is not fixed, primitive types have a fixed memory size and as four

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bytes long is eight bytes.

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Class types don't have a fixed memory, an object with 20 fields takes up more memory than an object

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with one.

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Generally speaking.

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An array of 50 elements is going to take up more memory than an array with one.

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For this reason, primitives cannot be null and class types can be.

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By the way, arrays are also objects as well.

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When you create a new era, you're creating a new object of the array class that can store elements.

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Everything is just happening behind the scenes.

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That being said, almost everything in Java is a class variable, an object.

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As long as it stores a reference, can be no can call methods, then it's a class variable.

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In this lesson, you learn to tell the difference between a primitive type and a class type, a primitive

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represent value and nothing more.

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It cannot be, no, and it doesn't have methods.

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Examples of primitive types are Ent., long car and boolean.

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A class variable story, a reference it can be no, and it can call methods, examples of class types

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that we created objects from our scanner dealership and car.