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This is the name of our package.



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I need to actually create another class.



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So just click on this package here and then click on find new and then click on Java class.



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So for the name of the class just type in here chat and then click on OK.



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As you can see this is our catch class.



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So just click on this package here again find new double class.



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So for the name of the class just type in here like in OK is our legal class.



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Again I want to create another class called Leppert.



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So just click on this package here for my new job class and here just typing Lebert OK again I need



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to create another class called Baird.



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So just click on this package here and then click on find new and then click on job class.



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So for the class name just type in here.



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OK.



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And then click on OK.



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So as can see here I created all of these classes.



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So now I can actually interact with these classes.



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OK.



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So now let's actually go inside the Animal class and as you can see here this is our Animal class.



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So let's actually double click on this animal that you have here in order to make this a little elevator.



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So as you can see here this is our Animal class.



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And first let me point out that are all classes in Java up directly or indirectly inherit from the Object



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class.



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OK.



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So as you can see here this Animal class actually inherits from the Object class.



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So if I actually put this extents object here so as you can see here this object class is actually inside



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the inside the Java that like package.



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Ok here I am actually showing you that this animal class is actually inheriting all of the features



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and behaviors that are inside this object class.



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OK.



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But if we actually don't put these two votes here that means that this animal class is actually inheriting



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from the Object class.



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OK you don't have to actually put this extends object here because that's UB by default or this animal



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class is actually inheriting from this object class.



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OK.



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So let's actually go inside this object class and see the behaviors that are inside this object class.



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So if you are using a match 6.



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Just hold the command key and then click on object.



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And if you are using a Windows machine you just need to hold the control key and then click on object.



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So as you can see here this is our object class.



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OK.



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And here you can see the behaviors and the features that are inside this class.



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Ok for example this Meffert equals or as you can see this is the constructor OK constructs a new instance



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of Object.



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OK.



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And other methods that you can see here finalize.



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OK.



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So notify.



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OK this is another method.



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So let's actually close this class here.



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And inside this animal class.



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Now we want to actually put my implementation's my own coats inside this class.



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Most of the program is actually taught or put.



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These two votes here extends object because by default our class is actually inheriting from the object



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class.



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So we don't need to put these words here.



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So not inside the curly braces I can put my own codes.



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So now I want to create some instance variables inside these animal class.



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So just type in here private as you can see the access modifier of my instance variable is private.



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And here I want to specify that my variable is going to be a constant.



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OK because I don't want to actually allow any other classes or methods to actually change the value



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of this instance variable.



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So I just need to put in the final keyword here.



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And then I need to specify the data type of this variable as strange.



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And then I need to give a name to this instance variable name.



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So as you can see here I didn't assign any value to this instance variable because I don't because I



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want to actually show you an important point about constructors in this tutorial.



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So as you can see it's now shown as an error.



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So let's actually Hulver our mouse pointer over the error area and see what's the added variable name



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might not have been initialized.



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So as you can see here it's complaining that we actually didn't assign any value to this instance variable.



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OK.



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So let's actually create another in another instance variable private.



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And again my variable is going to be a constant find all the data type of my variable is strange and



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the name of my variable is color.



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OK.



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And then I want to create another instance variable private.



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Now I want to create another instance variable.



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So the access modifier of my variable is private.



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And here my value is not and constant.



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So the data type of my variable is in it and the name of my variable is amount of speed.



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And then I need to.



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And then I need to put in a semi-colon at the end of my statement.



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And again I want to create another instance variable private int I'm out of power.



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OK.



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So as you can see here these are the instance variables that I created inside these animal class.



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OK.



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And as you can see here because we didn't assign a value to these are constants here.



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The Android studio is actually complaining.



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So now I want to actually create a constructor for this animal class.



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OK.



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So first I need to specify the access modifier of my constructor public.



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OK.



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And the name of my constructor must be the same as the name of my class.



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OK.



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And.



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And then I need to put in a pair of round brackets after my constructor name.



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And then I need to open and close my constructor by using D-school curly braces.



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OK.



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So inside their practices here you want to specify that this constructor is going to actually accept



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some arguments.



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Ok so my first argument is of type as strange and the name of my argument is name.



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OK.



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My second argument is of type as three and again and the name of my argument is color.



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My favorite argument is of type int and the name of my argument is amount of speed.



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OK.



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And again the later type of my argument is int and the name of my argument is amount of power.



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OK.



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So as you can see here these are the arguments that I specified for this constructor here.



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OK so now I want to actually initialize these instance variables.



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OK.



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So in order to actually refer to these instance variables inside this constructor are you need to putting



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this key vote here.



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OK.



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Because the name of this instance variable is actually the same as this as the name of this argument



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here.



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I need to put the key word this here in order to refer to this instance valuable insight this constructor.



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OK so does that name assignments operator name ok.



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Does that color assignment operator color.



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OK so this color here actually refers to this instance variable and this color refers to this argument



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here.



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OK so because the name of this argument here is the same as this is the same as this instance variable



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here.



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I needed to actually put this key word here in order to refer to this instance variable.



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Ok so this key vote here actually refers to this class.



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OK.



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So this thought color assignment operator color.



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OK.



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And again does that amount of speed.



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Assignment operator I'm amount of speed.



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Does that amount of power.



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Assignment operator.



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Amount of power.



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And then I need to put in a semicolon at the end of my statement.



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OK.



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So as you can see here now the arrows are gone.



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OK.



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So here I initialized these instance variables and now the error is gone.



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OK.



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So whenever that I want to actually create an object from this animal class to this constructor it's



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going to be called.



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OK.



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And then I need to specify a value for these instance variables.



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OK if I don't actually specify any value for this instance variables I cannot create any object from



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this animal class.



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OK.



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Because it is because this constructor is going to actually accept some values and that values is going



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to be assigned to these instance variables.



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OK so hopefully that makes sense.



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Now I want to actually create the getters and setters for these instance variables because as you can



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see the access modifier of these instance variables is private.



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OK so I need to actually create some are Hera's or setters in order to allow other classes to actually



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set or get the values of these instance variables.



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OK.