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

What is my personal agent, What is "My Personal Agent"? My personal age...

What is "My Personal Agent"? My personal agent is a computer programme which work automatically and have voice interface.

The software or script to scan automotive ads, The software or script to sc...

The software or script to scan automotive ads Project Description: Looking for a company that made the script or application to search through pages of listings of automotive

Illustrate about the java runtime environment, Java Runtime Environment (JR...

Java Runtime Environment (JRE) Java Virtual Machine is a part of a large system i.e. Java Runtime Environment (JRE). Every operating system and CPU architecture requires dif

What is meant through semantic error, What is meant through semantic error?...

What is meant through semantic error? It is an error that a developer encounters while a statement is executed but it was not intended through him (the developer). Such errors ar

List the java class library, list The Java Class Library? Java holds an...

list The Java Class Library? Java holds an extensive library of pre-written classes you can use in your programs. These classes are separated into groups known as packages. Th

Need Project Ideas.., I need some Unique Idea About my final Year Project ....

I need some Unique Idea About my final Year Project . It could be a Website or an Android application. I want to create Something very unique which in some sense benefits a society

Jsp retrive data, how to retrive data in one block from database by click ...

how to retrive data in one block from database by click data link in another block

Android app for evaluating of distance, Android app for evaluating of dista...

Android app for evaluating of distance Project Description: The request is to prepare an app for Android. The application needs to run on tablet (7 "or larger) and the layout

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