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

I have javascript work, I have JavaScript work Project Description: I...

I have JavaScript work Project Description: I need an annonation type tool added It should be incredible simple for a good js coder. But there will be a custom design and

Develop a shopping carts application , To develop a shopping carts applicat...

To develop a shopping carts application for an online store of your choice Outcomes: 1. Apply the GUI components of Java and other tools to create user-friendly interfaces.

Component developer to code in java, Component Developer to code in Java: ...

Component Developer to code in Java: Worked for Sansri's Gateway as Software Engineer . Here I Worked as a Component Developer to code in Java and J2EE technologies Here Ensu

Cadence design systems, Cadence Design Systems:   Role Working ...

Cadence Design Systems:   Role Working on tickets including debugging of unix based applications Installations of unix based tools/utlity Installation

What is a pointcut, A pointcut is something that describes at what joinpoin...

A pointcut is something that describes at what joinpoints an advice should be applied. Advices can be applied at any joinpoint that is supported by the AOP framework. These Pointcu

What restrictions are placed on method overriding, What restrictions are pl...

What restrictions are placed on method overriding? Overridden methods must have the similar name, argument list, and return type. The overriding method may not limit the access

Need software to print bills on a4 pape, Need software to print bills on A4...

Need software to print bills on A4 paper in the format provided. The details are shown below - 1. Serially generated Invoice Number. 2. Appropriate fields in the invoice have

Define object lock and which kinds of object have locks, What do you think ...

What do you think about an object's lock and which kinds of object's have locks?

Javascript validation, 1. Obtaining the new script: Download and save the...

1. Obtaining the new script: Download and save the attached comment CGI mailer script form-mail2.pl to your server's cgi-bin directory, and change the permissions on the script t

Intro to Programming, Overall Requirements Every phone number is broken up ...

Overall Requirements Every phone number is broken up into sections as shown below: Country Code Area Code Prefix Line Number 1 919 882 5000 Write a program to separate out a ph

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