some questions, please answer it

[ishan kalra]

hi,

i have encountered some questions, please tell me the exact answers

13.Which two techniques can be used to provide polymorphic behavior? Choose two

�Extending a class and adding a new method
�Implementing two interface in same class
�Extending the class and overriding a existing method
�Implementing a interfaces with several different classes


i am sure about 3rd option what other ?

[Bear Bibeault]

What are your answers? We don't do people's homework for them here, but you can get help with doing it yourself.

Start by taking your best shot at the answers.

[Cameron Wallace McKenzie]

The word polymorphic means many forms (poly = many, mophic = forms).

So, polymorphism happens when an object can take on many forms. It really has to do with the instance that is created.

So, a person is a mammal, and an animal - that's two forms they can take on. A person can also be a spouse - that's another form they can take on. A person can be a dentist or a programmer - those are other forms.

In this scenario, if person were a class, maybe mammal would be a superclass, and perhaps animal would be an ancestor class. Spouse, programmer and dentist all seem like roles to me, so those might be modelled as interfaces.

So, extending a class, or implementing an interface, are ways that an instance of a subclass or implementing class can be polymorphic. That's what polymorphism is all about. Now, how that applies to your question is another story.

-Cameron McKenzie