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    <blockquote> <p>As every class in Java extends from Object, so it should have clone method but still we are forced to override clone</p> </blockquote> <p>No you are not forced to override the <code>clone</code> method. In inheritance, when you inherit a class, you are not forced to override it's method. Its modifier being public or protected doesn't make much of a difference. However, if you want to invoke a method directly on <code>super</code> class reference, then that method has to be <code>public</code>. Protected methods are accessible only through inheritance. That is you can only access them through <code>subclass</code> reference. Or if you override the method, you can access them through <code>super</code> keyword.</p> <p>Having said that, you should not override <code>clone</code> method, as it is <code>broken</code>. Because, for a class to be cloned, you need to implement the <code>Cloneable</code> interface. And then your class uses the <code>clone</code> method of <code>Object</code> class instead. Because, <code>Cloneable</code> interface doesn't exactly have any method for <code>cloning</code>. It would be a better option to use <code>Copy Constructor</code> instead. </p> <pre><code>public class A { private int data; public A() { } public A(A a) { this.data = a.data; } } </code></pre> <p>For more details, I would suggest to go through this chapter of <code>Joshua Bloch's</code> Effective Java, which covers all aspects of using <code>clone</code> method.</p> <p><a href="http://my.safaribooksonline.com/book/programming/java/9780137150021/methods-common-to-all-objects/ch03lev1sec2#X2ludGVybmFsX0ZsYXNoUmVhZGVyP3htbGlkPTk3ODAxMzcxNTAwMjElMkZjaDAzbGV2MXNlYzQ=" rel="noreferrer"><strong>Effective Java- Item # 11 - Override clone judiciously</strong></a></p>
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    1. COAs you wrote that "No you are not forced to override the clone method" but I can't call clone directly on the object if clone is not overridden. Why is it so?
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    2. CO@anand. For invoking any method of `super class` you need an instance of that class. Now, if you override the `clone` method, you have that instance of `Object` class as `super`. So, you use `super.clone()` to invoke it.
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    3. CO@anand. Also, you cannot directly call `clone` method on instance of `Object` class, because `clone` method is `protected`, and is only accessible in `base class` through `inheritance`. So, you can invoke it through the instance of the same class. But be aware, you need to handle `CloneNotSupportedException`
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