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Let's not look at something called this reference earlier we did this in mission statement which basically

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allowed an object to invoke one off its overloaded constructors that is from within one constructor

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to access an overloaded constructor an object uses this in location statement.

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This reference is also related to an object.

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And that's what it is when to access variables are methods of an object we use it's object of friends

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followed by dot operator which is in turn followed by the variable or method name.

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But it's an object wants to access its own members.

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That is not members of some other object but it's own members.

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In that case it can use this reference.

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And for that you would use the keyword this followed by dot operator which is then followed by the variable

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Armatus name.

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So this reference is basically an object reference but it is just that it's a reference to the current

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object itself.

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Not that we have this reference an object can also access its members directly.

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So the next question would be why then use this reference when you can access the members directly.

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The real use of this reference is when we want to access instance variables that are hidden by local

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variables which are defined in a method or constructor.

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Let's look at an example to see what it means for a variable to be hidden or shadowed.

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Which is just another term for hidden.

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In this example there are two instance variables ID and name.

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There is also the method abrade profile which has two parameters.

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New ID and name.

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So one of the instance variables and one of the method parameters shared the same variable name.

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CORNYN good to this.

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We say that within the method update profile the method parameter name is hiding or shadowing the instance

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variable called name on any reference to the variable name from within the abrade profile method is

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actually a reference to the method parameter a Nonda instance variable.

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So if you want to access the instance name from within the upgrade profile method you would have to

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use this reference.

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That is you would say this not name as shown here.

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However if instance variable is not hidden by any local variable then the instance variable can be accessed

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directly as we can see here in this particular statement where ID field is being assigned new ID just

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know that this reference can also be used in constructors.

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Also as I mentioned earlier this reference can be used to access methods in the current object.

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However since there is no hiding of instance methods like in the case of instance variables you don't

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have to do that.

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You can access the methods directly.

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So normally you would use this reference when you're accessing or need instance variables which are

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hidden.

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Finally note that this reference cannot be used in a static method.

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If you recall our discussion on static methods we say that there are class methods and so they don't

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deal with objects and that is they cannot access instance variables or instance methods defined in the

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same class.

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So this means that you cannot also use this reference within static methods as this reference is used

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to access.

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Instance variables are instance methods.

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Let's actually take a look at this in the code.

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Look here we are in the basics democracy.

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Let's first define an instance with a bill here.

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Let's just call it as ID and Ledgard have the default zero.

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I just try to access it from the static method which we wrote earlier.

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In fact all our methods here in this class are static.

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So let's define a variable.

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I.

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And let's use this reference to access the instance variable.

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So this should give us a compilation error.

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So I'm in the basics directory let's just compile it.

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So it's it's it gives a compilation error under-dressed non-static variable which means it's an instance

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variable does.

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Since this isn't a variable here it cannot be a reference from a static context where context implies

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it's a static method static context implies static method.

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So it's just it's not an instance variable.

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This cannot be reference from in static context.

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OK so we cannot access it.

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And if you want we can also remove this iron.

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We get a similar because.

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Instance variables can be accessed directly but since it's a static method it still gives us a compilation

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error on your chest non-static variable which means the instance variable ID.

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So in this case it's an ID.

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It cannot be referenced from as static context.

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OK so we cannot access any state from static methods.

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OK so that's about it.

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And next we'll be doing a demo on and then we will use this reference.

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So we will will be using this reference in the demo.

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OK.

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So that's about it.

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And thank you