Explain subclasses and polymorphism, JAVA Programming

Assignment Help:

Explain Subclasses and Polymorphism ?

Car and Motorcycle are subclasses of MotorVehicle. If you instantiate a Car or a Motorcycle along with new, you can use in which object anywhere you can use a MotorVehicle, since cars are motor vehicles. As same you can use a Motorcycle anywhere you can use a MotorVehicle. This use of a subclass object in place of a superclass object is the starting of polymorphism. I'll say more about polymorphism later.

The converse is not true. While all cars are motor vehicles, not all motor vehicles are cars. A few are motorcycles. Thus if a method expects a Car object you shouldn't provides it a MotorVehicle object instead.

Remember that I said you shouldn't provide a method in which expects a Car a MotorVehicle. I didn't say you couldn't. Objects can be cast into their subclasses. This is useful while using data structures like Vectors that only handle generic objects. It's up to the programmer to remain track of what kind of object is stored in a Vector, and to use it accordingly.

The proper choice of classes and subclasses is a skill learned primarily by experience. There are often different ways to define classes.
toString() as example of polymorphism


Related Discussions:- Explain subclasses and polymorphism

Program for sorting algorithm - java program, Introduction: In this pr...

Introduction: In this project, you will explore a few sorting algorithms. You will also test their efficiency by both timing how long a given sorting operation takes and count

Use the constructor, Can we use the constructor, instead of init(), to init...

Can we use the constructor, instead of init(), to initialize servlet? Ans) Yes. Of course you can use the constructor instead of init(). There's nothing to stop you. But you sho

What are access specifiers available in java, What are Access Specifiers av...

What are Access Specifiers available in Java? Java has four access specifiers, which are enlisted below: Public: public methods, classes and fields can be accessed by ever

Eclipse javaj, how to write coding for money and currency

how to write coding for money and currency

Cryonic labs, Cryonic Labs Project Description: Seeking people to col...

Cryonic Labs Project Description: Seeking people to collaborate with in designing gaming apps and mobile apps for the Android Market. I'm presently a student in Computer Engi

Why you don''t need to import java.lang.*, Why You don't need to import jav...

Why You don't need to import java.lang.* There is one exception to the import rule. All classes in the java.lang package are imported by default. Therefore you do not required

What do you mean by auto wiring, The Spring container is able to autowire r...

The Spring container is able to autowire relationships among collaborating beans. This means that it is possible to automatically let Spring resolve collaborators (other beans) for

Explain difference between an if and a switch statement, What is the differ...

What is the difference between an if statement and a switch statement? The if statement is used to select between two alternatives. It uses a boolean expression to decide whi

Write a note on java beans, Question 1 Explain the data types in Java ...

Question 1 Explain the data types in Java Question 2 Write a note on StringBuffer Question 3 What is Exception? Question 4 Write a note on stream classes Questi

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd