Interface with two different implementations

Question

I have an interface Person and I have 2 classes Female and Male that implement the interface.

For the Female class, I have a method getPregnancyMonth that my Male class does not have. Adding that method to my interface Person becomes a problem as my Male class now needs to inherit that method from the interface; but the male would never be pregnant.

What would be a solution, do I need to extend Person instead of implement?

EDIT: Sorry if my question wasn't clear. In this case I have added both get/set methods from the Male and Female classes to the interface.

    static void Main(Form form) {
        Person person = Factory.createPerson(form.getGender());
        person.setName(form.getName());

        if ("F".equals(gender)) {
            person.setPregnancyMonth(form.getPregnancyMonth());
        }
    }

My question is, since my interface has getPregnancyMonth, my male has to add that method to the concrete class to implement the interface. Is there a way to avoid this?

Answer 1

getPregnancyMonth Should not be in the interface of Person.

Personally...no pun intended...I think you should create Person as an abstract class as female and male will share a lot of the same attributes and functions.

Then you could create Female and Male interfaces that reflect unique functionality for each sex.