Clone method behavior at memory level - java

Question

when i am creating new object of Particular class using new keyword it occupies some memory in heap For example i have class Xyz and i am creating object of Xyz using new keyword and it occupies some memory in heap

Xyz xyz = new Xyz();

now assume that xyz have memory location 12@FFD

same object create using clone method

Xyz xyzClone =(Xyz) super.clone()

my question is if xyzClone occupies different memory in heap than xyz than why we need clone method we can achieve same behavior using new keyword ??? and if xyzClone occupies no extra memory than it may be behave like Singleton

Please clear my confusion why we need clone method ???

possible duplicate of http://stackoverflow.com/questions/5802118/why-we-use-clone-method-in-java — Santhosh, Nov 17 '14 at 05:49
@JigarJoshi : i clearly mention that assume that we have some memory location.my quesion is why clone — Nirav Prajapati, Nov 17 '14 at 05:49

score 3 · Answer 1 · answered Nov 17 '14 at 05:48

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clone() creates new instance which has same state as the one from which it is cloned

answered Nov 17 '14 at 05:48

jmj

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score 3 · Answer 2 · edited May 23 '17 at 11:57

Creating a Object#clone means you can create an object that is similar to another object but is not the same object.

By this when you say you have cloned an object, it means that there is a different object in the heap that has the same state. But if you alter this new object, it does not alter the original object

my question is if xyzClone occupies different memory in heap than xyz than why we need clone method we can achieve same behavior using new keyword ?

the clone() copies the values of an object to another. So we don't need to write explicit code to copy the value of an object to another.

The copy constructor is used to create a copy of an object that is passed by value to a function. This is not an issue in Java, because all objects in Java programs are passed by reference.

If we create another object by new keyword and assign the values of another object to this one, it will require a lot of processing on this object. So to save the extra processing task we use clone() method.

See also :

If you alter the new Object which has another object then it will alter original. Default clone does shallow copy. — Deepu--Java, Nov 17 '14 at 05:58
@san De cruz : ok got your point have one doubt in mind if clone is not memory efficient than why we use it in prototype design pattern — Nirav Prajapati, Nov 17 '14 at 05:58
@NiravPrajapati I hope last thread in my answer clears the point — Santhosh, Nov 17 '14 at 06:02

score 1 · Answer 3 · answered Nov 17 '14 at 05:50

1

Yes, you can implement the same functionality like clone by creating any new method in class. But clone gives you more control. By clone you can create shallow copy(default) as well as deep copy(if you want).

It's just in-built functionality of Object class which gives you control on object cloning.

answered Nov 17 '14 at 05:50

Deepu--Java

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can we make over program memory efficient using clone method – Nirav Prajapati Nov 17 '14 at 05:51

Clone method behavior at memory level - java

3 Answers3