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Next thing to understand with regards to inheritance is about what members of a superclass can be inherited

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by subclasses.

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And this is dictated by access modifiers defined for those members which is cost access modifiers when

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covering access levels and packages.

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They were discussing about how one class can access other classes members.

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But here we are talking about members that are inheritable except for one access modifier where that

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is the purpose that access modifier.

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There is no difference when it comes to accessing members of a class versus inheriting membership across

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Britain or discussed Perpich remembered in detail as we did not cover subclauses at that instant of

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time so protected modifier will be discussed in detail in this lesson.

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This is an important topic not the end of the discussion.

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I'm going to use some code to demonstrate this in the clearest possible way.

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So let's look at the actual money first on how they can affect inheritance undergrad also serve as a

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refresher to what we discussed earlier when other packages help and meaningfully organizing our classes

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.

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But as classes within a package will form similar kind of functions.

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Sometimes some of these classes may interact with each of them however sometimes they may not interact

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with each other but still provide a similar kind of functionality.

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So all of us think of classes in a package as one close knit family access modifiers that allow us to

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specify what data and behavior of a class is accessible to family members and non-family members or

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family members being classis in the same package while non-family members are process reciting outside

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of the package.

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We will use this notional homily to explain some of the stuff in this lesson on how to access modifiers

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which were discussed previously discussed private default and public modifiers as they don't behave

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any differently from our earlier discussion.

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The only difference is that protected Madhi where which is specific to inheritance and that we will

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discuss next facias private modifier a private member which can be a private mailable or a private matter

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of a superclass is never inherited by any subclass recalled that no class can ever access other classes

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play much at all.

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So no difference here.

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In the case of inheritance.

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Next is a member with default access level which means no explicit access modifier is used.

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Default means only classes in the same package can access it.

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That is only family members can access it.

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So with regards to inheritance a default member is inherited by only subclauses in the same package

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as the superclass.

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Also the subprocess can only let other family members to access the inherited members so it is correct

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to a major inheritance is involved or not a default member is never accessible outside the package.

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Next is public modifier public means anybody can access it or anybody can inherit it.

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If I inherited the inherited member can be accessed by anyone too that is.

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Anyone can access the inherited member by using the subclass name or subclass object.

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Nokomis interesting modifier that is specific to inheritance which is protected protected member has

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same access libellous.

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Default member but in addition it also provides special access to only subclasses.

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Outside of the package Supertech protected member is primarily for use only in subprocess outside the

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package ought to only family members on one or more of those family members can be subprocess to holler

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.

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One thing to remember is that the inherited protected member in a subclass should not be accessible

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to any non-family member that is any class that is not in the same package as the superclass should

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not access it.

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We are the boss.

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Hope that's clear.

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But let's look at code and everything should be clear after that.

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For the sake of convenience and browsers see it sometime.

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I'm going to show this to my and my Eclipse editor and we're going to use 5 classes spread across two

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different packages.

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The reason for using two different packages is to demonstrate inheritance across packages.

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That is how superclass in one package under subclasses can be in a different package the packages I've

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named as follows.

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One is Kondrat semantics Gweedore OOP Don't be one.

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And the second one is calm down.

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Semantics square dog OOP duck Pete.

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Previously the package name was Kondrat semantics griddata basics on basics of democracy was under Busiek's

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So there we were dealing with only language basic cities.

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So the package name was basics.

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But since we are dealing with object oriented programming I introduce this new package called OOP.

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OK and it has two packages P1 and P2 under five classes are under Java beyond our Java Sea one bit to

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unseat two class names ending with the suffix one going to the package be one.

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So even once even going to prevent the ones ending with do with the suffix do which is B to C to D going

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to the second package too.

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So now let's look at the first class.

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Are Java and de-classified different variables.

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So in this demonstration I'm just going to use variables to demand strict inheritance accessibility

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of inheritance but the same applies to methods also.

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And this way the words are declared as static members but it need not be static which means that static

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members are also inheritable.

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So the first variable has the access modifier private under his name just pirate member.

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The second one does not have any access modifier which means that it has default access level and it

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is named as default member.

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The third one is has protected access modified and it is nimblest protected member.

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The final one is public.

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Has public access modifier under it is named as public member.

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No see when dodgiest simply extends A-one OK and it demonstrates accessibility of members to the inherited

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members.

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Do job which is in a different package.

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Also extents.

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Even so if one is in one package under a subclass it is in a different package and do Java is just a

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regular class.

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It does not extend even understood regler regular class but it demonstrates accessibility of variables

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of members within A-one and doors that have been inherited in C so it also tries to access them and

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also in C to also be true that Java is also like beyond or Java.

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So it does not extend any class and B to C to out in the same package and it is also introduced just

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to show accessibility of variables in a run.

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And also the in and also to show how it can access variables that are inherited by C too.

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OK so let's just begin with the first one which is a direct member.

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So let's go to see one or Java and let me just uncommon this so C one is simply extending a one.

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And here we get a compilation error.

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When I holler what it is a feel A-one not direct memory is not visible.

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So we know that private members are always private to the class itself so they are not inheritable.

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I also they are not accessible from a different class.

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So that so that's why if you're going to be taught Java on the file uncomment does class.

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It says that one book pirate member is not accessible.

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And of course same would apply for them both.

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But once you do so on we don't have to test that.

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Now let's go into one.

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Let's try the next one which is default remember it's going to see.

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Let me uncomment this and as you can see we still have the completion error because see too and it went

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out in a different package and the default member which is defined and even is not accessible to because

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default member is accessible only within the same package as a win.

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So only to add to family members right.

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But if you're going to see one or Java as you can see in this document default member is X is inherited

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.

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That's because you run and it went out in the same package.

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And moreover the default member is accessed directly.

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Right inherited members can be accessed directly now from being under Jawa you can access.

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Default member.

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Why not a one.

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Because be run on are in the same package.

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But interesting thing is that you can also access the inherited members to an inherited de-funded member

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so you can access it YRC run also so both of these are possible.

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And next is protected member.

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So let's going to see to and as you can see the protected member is inherited by C too.

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Even though C is in a different package so it can access a protected member So that's the main benefit

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of declaring a variable as a protected right.

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If it can be accessed by any subclass under subclass need not be in the same package.

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Now that's going to be to do our Java and B cannot access the protected member in a one so protected

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protected member has protected access level and it cannot be accessed so we get this compiler error

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.

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Now if I uncomment the second statement which is trying to access protected member YRC too.

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So C to inherit protected member but it is still not accessible from B to and would be said that the

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reason for that is because BE2 is not a family member.

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Even so B is not in the same package.

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Even so we discuss that also.

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So let me just comment this back and let me go in to see what seaven.

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Also can inherit the protected member you know that I don't see when it went out in the same package

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back from B run.

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You can access a protected member also is like a default member right.

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It has the same access level on B when he went out in the same package so it can access protected member

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.

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It can also access the protected member YRC one so see if one is inheriting this protected member on

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it can access it and see do you know that is in a different package and it is inheriting protected member

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.

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But Beaven is able to access or was not able to access it YRC do but be one is able to do it.

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That's simply because A-one and B1 are on are one family and so that is that in the same package and

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Beaven has the privilege to access protected member even YRC.

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OK.

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And the final one as a public member and public ments.

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Anybody can access it and anybody can inherit it.

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So C-2 can access here directly.

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Which means you can inherit it and is able to access it directly and you also can access it from using

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A-one and also using C-2.

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So that's the benefit of being public so early that it was not able to access YRC to the protected member

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while you do but the public memory can access.

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So public is cruelly public it's part of the API.

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Now see one also can access a public member and be one also can access public members either using one

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or see one.

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So that's about it.

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The nice thing is we could also demonstrate not just our members that are inherited but also accessing

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those members and the non-stop Grothus also accessing those members.

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And that's it