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

In which way java says write once run anywhere, Java says write once, run ...

Java says write once, run anywhere . In which ways this isn't quite applicable ?

I need java expert with tomcat tuning experience, I need Java expert with t...

I need Java expert with tomcat tuning experience Project Description: Require a Java expert to fix memory issues with tomcat. Skills required: Java, Apache

Ajax- html- xml- css and tomcat used in java, AJAX- HTML- XML- CSS and  To...

AJAX- HTML- XML- CSS and  Tomcat used in Java: Project Title: Zee Ads   Role                       : Developer Domain                  : Web Ads Environment

How does an exception permeate through the code, How does an exception perm...

How does an exception permeate through the code? An unhandled exception moves up the method stack in search of a matching When an exception is thrown from a code which is wrapp

Difference between the file and randomaccessfile classes, The File class en...

The File class encapsulates the files and directories of the local file system. The RandomAccessFile class gives the methods required to directly access data contained in any part

Connect 4 game application, This assignment is a good project for working w...

This assignment is a good project for working with 2 dimensional arrays. In this program, you will implement an ascii version of the classic game "Connect 4". Connect 4 is a 2 p

We are in need of programmer, We are in need of Programmer In search of ...

We are in need of Programmer In search of someone who know java well enough to work under my in-house programmer and take work form him to keep the project moving. The project d

Sudoku class used in java program, Sudoku Class (Simple Version) The ...

Sudoku Class (Simple Version) The Sudoku class will encapsulate the minimum necessary data and logic to manipulate, print, and set the SudCells , in anticipation of a high

Describe overriding methods, Describe Overriding Methods ? Assume that...

Describe Overriding Methods ? Assume that one day you've just finished your Car class. It's been plugged into your traffic simulation that is chugging along merrily simulating

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