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So we have seen how method writing is implemented.

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And let's not forget what cannot be overridden.

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And there are three things that cannot be overridden on the first one is a final method.

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I that there is simply not my limited but it is declared the.

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Key word final in its declaration.

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We looked at final variables which meant that if variable's value once initialized can never be changed

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that is the variable true value is final.

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Similarly if finden method behavior is also final so cannot be overridden.

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You will do this if you have written some logic.

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You want it to work only in the way you have implemented it.

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That is not of the subprocess should ever be able to redefine it next.

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Fields cannot be altered and that is buttstock as well as instance variables cannot be overridden.

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If you recall a discussion on method or writing we said that an instance variable in a superclass can

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be hidden by an instance variable in a subclass by really declaring that we reachable in the subclass

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.

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That is a really clear variable.

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They will have the same name as in the superclass.

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On other things like variables Deedat I do not matter.

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Only thing is they should have the same name.

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Not a good question to ask would be why are instance variables not overridden by then instance methods

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can be overridden.

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Why did the language designers do that.

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My best guess is that here we are talking about two different entities.

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One is data that there is behavior.

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Now when it comes to behavior that is the methods it makes sense to pick the more specific question

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of the behavior with respect to the object in context.

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An GBM is just doing it.

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That's because inheritance is mainly about having classes of it more specialized logic.

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So you would execute a specialized writing matter.

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I would assume semantically same does not hold hard data that is Duffys.

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What I would value the current be has in the current class is good enough on practically That would

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be the most probable scenario.

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Dutch studies and why language designers would have gone with this kind of behavior.

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So no need to go down the hierarchy and become more specific you.

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So that's the reason why.

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Instance variables are also early bonder but not that incased a subclass object.

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Instead of re declaring simply resigns will be a different value then we will see that value as there

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is only one motion of the variable next tactic that cannot be overridden in the rest of the lesson.

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Let's see why static methods cannot be overridden and the same argument would also hold forth static

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variables.

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At the end of the lesson we will do more of static methods not being overridden and in the next lesson

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we will do a quick demo all priest not being or what he can do.

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Let's consider it our familiar inheritance tree and I made minor changes here for the sake of this discussion

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in the User class.

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Same we see a book methods have been removed and a new method called static method has been introduced

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in book user as well as stuff process on both methods are static methods.

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Now here we have this declaration where we are creating an instance of editor under referenced by Peary's

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user.

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We are going to invoking Silverlink method which would invoke the same blink in the User class Nona's

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as you say blink done in books posted of your method and this gives vino that posted Abele method.

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In the staff class would be invoked as opposed to post-edit view.

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End User class and we know that it's because JVM searches for the most specific words shown off posted

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a view method starting from edit class as the object here is editor.

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Let's also assume that save blank also invoke static method.

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In this case the static method in User class would be invoked not the notion in the staff class a static

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method are not overridden so static method in the same class is being invoked.

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So here the class user is saying that I'm defining this method call Silverlink And if this method accesses

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an instance method then I'm not going to get involved as I don't deal with state.

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So the instance method to be invoked will be decided by JVM at runtime based on the object in context

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bugger this good exercise one of my starting my turret's then it means that I want to access the static

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method that is defined in my class as startlement that belong to me.

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I don't get if the subclass object on which this method is invoked also has a similar static method

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.

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So I'm E-Class and if my code uses my class methods then my intention is to use my class matters not

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somebody else's down the class hierarchy.

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So that's a nice way of looking at this behavior.

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But from a one method binding lesson we also know that stocktake matters are bonded compile time itself

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and so the invocation of the static method is bownde at compile time itself.

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So that's another way to look at it later in the day.

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We will actually see this in action to get some more clarity.

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Let's also look at an example where support classes have stopped instance methods that identical names

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here.

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How close super with one static method call it on one instance method called be and there are three

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subclasses extending the superclass and they all have the same methods that are in the superclass not

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Ajume duck.

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We have this method foo class parameter.

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S is of type super which is the superclass inside the method we are invoking both methods E and B on

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the input reference variable S then method is invoked.

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It will always invoke the static method in the superclass regardless of the object that gets assigned

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to the input variable S that is you can invoke the method for any of the three subclass objects or even

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the superclass object on only the method in superclass gets in.

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As we discussed earlier the reason for this is there is a static method on stocktake but dirt's are

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bounded at compile time based on the referenced type.

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So the compiler precisely knows which method is invoked on blocks a static method in any of the subclasses

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.

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You just need to use the subclass named directly order reference type has to be offcuts Stop-Loss type

87

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or you would need to apply a cast where the cast is off suppressed like Hollywood when it comes to in

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Woking matter b.

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And the second statement.

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The method invoked the rarely depend on the object that got passed.

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And we have seen this while discussing polymorphism.

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So if an instance of subline is passed at runtime then each version of method B which is overriding

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the motion in superclass is invoked if an instance of sapu is passed then its motion of method being

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invoked.

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But if super object is passed then the motion in super is invoked and we already know the reason for

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this.

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The method to be invoked will be decided at runtime based on the object type of the reference variable

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.

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We know that JVM invokes the more specific motion of the method.

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So unless starting my third there is no one single word of method B that gets executed in the method

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for.

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It just depends on which object is passed.

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Static method which is the method to be in go is finalized right away at compile time itself to reference

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type.

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And so what writing does not apply here.

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The object if it comes into play at runtime is totally irrelevant.

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Also note that just like in the case off topic an instance variables we said that he had this topic

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matter in a subclass is hiding the static method in the superclass or not let's look at some more details

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on syntactic methods.

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And already this was mentioned earlier Superguy word is related to objects so it cannot be used inside

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a static method.

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If you have to access a hidden superclass method then you'll need to qualify the method name with the

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super Krosnick unrealistic mollify.

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It simply means superclass name should be followed by dog operator which is done followed by the mean

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.

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Next we know that static methods do not how and it can grow without it.

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So just like the way a static method cannot access instance variables an instance method Dick cannot

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hide instance methods and we get a compiler error if we try to do this.

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Finally static methods cannot be overridden by instance methods.

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And once again we get a compiler error.

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If we tried to do this so that's a bog on why static methods are not overridden.

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Nice thing is instead of simply accepting that starting methods are not overridden we kind of look at

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why they are not overridden and that is more important non-North look at a very quick double on the

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stuff that cannot be overridden.

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OK let's look at final metrics.

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We know that final methods can not be overridden.

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So here we are and users are Java and this is a final method that we have created.

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It's named as final method on your to an instance method.

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Find an instance method on here you can see the keyword final which means that this is the final version

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of the matter and should not be overridden.

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Now start of July which is the subclass of user B have a new method here and instance method we just

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call it has finally met method once again because we want to see if we can override it.

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And now we get a compiler error.

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It says cannot or I don't find one method from user so that you cannot write find other methods.

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Now let's look at stocktake metrics.

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Static methods cannot be ordered and they can only be hidden.

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So here this is the method from the method binding demo and it is called a static method and we have

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this print statement.

139

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It's just printing the method name along with the class name.

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So it's a static method now and stuff got Jawa.

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Also I created a new static method and it has the exact same signature and it looks exactly the same

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.

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Only thing is the print statement says it is from stuff not in user test or Jawa.

144

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So we have created this instance of editor and a reference type is user.

145

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And here we are invoking the topic matter right.

146

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So let me just run this.

147

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So as you can see the work and end user is getting invoker.

148

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That's because of early binding.

149

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Right because static matter is not overridden and because of all because of early binding which we have

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seen not method binding the notion in use it gets in Wilker because the reference type is what matters

151

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here.

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It looks at the reference type.

153

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The compiler looks at the reference type and it decides that the motion and met user should be invoked

154

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.

155

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And that's because of the early binding.

156

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OK now if you want to invoke the motion and static method then we can do this.

157

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Basically we are applying a cast and the cast is a subclass which is a stop.

158

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So let me run this.

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Our knowledge system tactic method static methods can never be ordered and it can really be hidden.

160

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So this is another example.

161

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Here we are invoking the Silverlink method using the style reference ironed Silverlink as defined here

162

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in the User class in the superclass and it simply prints undented in to post edit your method.

163

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So this we have already seen and in one of the earlier demos.

164

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So this would work.

165

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The posted of your method in the subclass.

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There is a posted of your method here which is an instance method on that instance method is already

167

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written and in the staff class so there is a poster posted here.

168

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So this is going to override that.

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But the method is going to work this way even though it is getting invoked from sibling.

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It's going to invoke this and that we know it's because of late binding because it uses the object type

171

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so that we already know.

172

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Then the interesting thing is here the static method is invoked one second the static method in the

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user classes invoked.

174

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But now it's not going to invoke the static method in the subclass.

175

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It's only going to invoke the static method in the same class.

176

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So this kind of illustrates that for days for posted if you mattered it's going to involve the motion

177

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in the subclass.

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And that's because of the object type.

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But for this when it comes to start big matter it is going to invoke the Stop the method in the same

180

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class not the one in the subclass.

181

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So this kind of a monster is that.

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So let's just go ahead and run this here.

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So this is the first quarter save eyeblink and Silverlink is in the post-edit view and because of the

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object type.

185

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The one direction stuff is getting in.

186

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But the Russian stuff is actually invoking the version and use it also so the user is getting in.

187

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So that plus part of the demo that we hired for material were writing.

188

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So that's for the instance my thoughts on when it came when it involved this topic matter it in the

189

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wash and end user not the one and stuff.

190

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So that kind of shows the difference between the two.

191

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Soit was invoking the word topic matter in the same class etc..

192

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So that's about it.

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That's about what cannot be ordered and