Enthuware

I think its also need to add calculateArea() call to constructor, because after constructing instance data will left inconsistent.

Russtam wrote:I think its also need to add calculateArea() call to constructor, because after constructing instance data will left inconsistent.

I agree

That would be required if the question were asking you about the invariant i.e. area must be consistent with the length. As of now the question is only about encapsulation.
I have updated the constructor to update area as well in any case.

thank you for your feedback!
Paul.