使用new（）运算符创建对象是否是多态性？

Question

Recently I attended an interview and a question was asked to me

Is creating an Object using new() operator is polymorphism?

For ex:

Employee e = new Employee();

Is this polymorphism? (Reply with yes and no and explain.)

I was unable to think of the answer.

As what i have read about polymorphism is compile type and runtime.

Can anybody explain? Thanks.

Answer 1

If you assign a base class reference to a child class object then it is a form of polymorphism.

Polymorphism, which etymologically means "many forms," is the ability to treat an object of any subclass of a base class as if it were an object of the base class. A base class has, therefore, many forms: the base class itself, and any of its subclasses.

This is NOT an example of polymorphism

Employee e = new Employee();

but assume if Empolyee is a class, which is extended from another class called Person then this will enable polymorphism by calling the methods of Employee at the run time:

Person p = new Employee();

Read this article to learn more:

http://www.artima.com/objectsandjava/webuscript/PolymorphismInterfaces1.html

Answer 2

According java polymorphism

The dictionary definition of polymorphism refers to a principle in biology in which an organism or species can have many different forms or stages. This principle can also be applied to object-oriented programming and languages like the Java language. Subclasses of a class can define their own unique behaviors and yet share some of the same functionality of the parent class.

Employee e = new Employee(); 

is not the example of polymorphism.
But

Object emp = new Employee();  

is an example for polymorphism.Since here Subclass ( Employee ) defining its own unique behaviors and yet sharing some of the same functionality of the parent( Object ) class.