Does subclass need to override Clone() method explicitly if superclass has already done it.

Question

If Class A extends class B and class B has already implemented cloneable interface then is it necessary for class A to declare 'clone() throws CloneNotSupportedException' .

I guess it should not be mandatory, as property to clone Objects of class A would automatically be inherited from Class B.

Answer 1

It is necessary to override clone() if class B defines non-primitve mutable member fields. These need to be deep copied explicitly within B.clone(). If B only contains primitive and/or immutable data members, A.clone() will do the job.

For a more detailed explanation, see this earlier answer of mine to a similar question.