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Next let's look at another widely used marker interface called Honorable from the Java dot land package

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.

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Even several classes in July that you package do implement Grown-Up an interface by implement inclinable

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class declares that its objects can read and their clients.

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That is there copies but copy we mean a duplicate object is written which would have the same state

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as the original object.

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But question is Where does this GRONING capability come from.

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Simply implementing Markin interface cannot magically do this whether the clone method in Object class

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is just the briefly mentioned does matter while discussing Object class.

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And we said that we will discuss it later.

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So let's look at it now.

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But convention tuneable functionality is implemented in this way.

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The class obviously should implement the marketing disclosable.

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Then you need to provide a method that supports cloning.

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Convention is to name the method as clone.

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But you can do a different name.

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Do you need to invoke the clone method in object to us since it's a superclass when we look use in the

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supercooled the current method in Object class would actually do all the heavy lifting on it and a copy

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of the object.

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However the copy it again would be of type Object and hence we need to cast it before returning it back

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to the caller.

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The clone method in Object class would check whether or not the current object implements global interface

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.

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If it does it would return a copy of the object.

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Otherwise it would throw an exception called Glue not supported exception.

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The Cricut end of that you see here and closing the method in location is related to handling of that

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exception.

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But let's not worry about it for now as we have not yet discussed exceptions.

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Note that if this method is not defined Bruening will just not work.

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Even if you have implemented Coonamble in the declaration you can simply end were blown metor on the

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object assuming it would directly involved the clone method in the object class that would not work

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as grown in Object class has protected access and hence can be invoked from only a subclass.

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So you need this kind of a method to support GRONING not that it's not necessary that you strictly have

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to invoke object classes clone.

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You're free to perform that cloning yourself.

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Finally the clone method performs what is called a shallow copy in order to generate a duplicate object

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shallow copy implies that when generating the new object defeating the origin an object or not Gloria

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did.

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Values are simply assigned to the corresponding fields in the new object had the fields been closed

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.

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Then we would call the process as deep copy.

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One problem that shall look up is that if a field is referencing a mutable object then Buddha origin

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an object as well as its clone would be referencing the same object.

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So if one of them modifies the mutable object then the other will also see the change.

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And that's not good.

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But if the fields are all primitives of reference in immutable objects then copy is not a problem.

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So if you know that there are any mutable objects.

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Then what you can do is once you get the grant from the superclass you can explicitly Glenda's in denial

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mutable objects and then read in the going back to the caller.

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Finally know that experts like Joshua Knoblock consider that it's a design flaw to have to enable as

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a marketing office.

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It would have been a mixing interface.

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As you can see the subclass is forced to implement a clone method in order to define the clone functionality

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.

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In that case why not have tuneable as a mixed in with gunas it's only meant that this is just because

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an item level in effective Java altered due to code the supplementary not for some relevant an interesting

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point on this topic.

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McGoohan very quick demo of the clone method.

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Here is a quote from the interview demo.

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You may recall that we have this class called X which was X turning abstract 8 I was also implementing

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three interfaces A B and C.

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So for this day I have introduced this global interface so it's implemented inclinable.

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And we also have this clone method which is exactly identical to what we have seen in this light.

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And so the goal is to create an instance an object of X and then invoke this method which would then

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return a clone off that object a duplicate of that object.

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So that is done from this method.

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This class desk.

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So here we are instantiating X and then here we are in working the clone method here the reference is

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C which is an interface.

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And it does not include the clone method.

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So that's the reason we have to downcast it we have to Buddhist typecast and then invoke the method

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and then the clone and then we get a clone object a clone and obviously that clone and the actual instance

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are two different instances.

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So they are not equal.

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And then this Gruinard should be brain.

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So let me just go ahead and compile and run this.

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So here it is.

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It goes on princedom grown created message that we see here.

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Now let me just go back to X. Let me comment this thing.

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If we are commandeers we need to get a clone non-supported exception because that's the check that not

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that that a clone method in the object class makes.

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So here we are invoking the going into object and that would make a check.

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And since Grown-Up it is not and is not implemented here we should get a trick or an exception.

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So the American public as you can see the clone method here in the object class is throwing this exception

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called clone non-supported exception.

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So that's that's what is being presented here.

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And that's about it.