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

Maintenance and administration activities, Maintenance and Administration a...

Maintenance and Administration activities: Name                        : e-Commerce OS and Soft wares    : Websphere 6.0, IHS, Unix, Weblogic 8.1   Maintenance an

Nested if.., WAP to input a 4 digit no and find greatest using nested if

WAP to input a 4 digit no and find greatest using nested if

Describe the relational operators in java, Describe the relational operator...

Describe the relational operators in java? Java has six relational operators which compare two numbers and return a boolean value. The relational operators are , > , , >=

Boggle Game, any one out there with Boggle Source code?......i really need ...

any one out there with Boggle Source code?......i really need it guys please.

Simple sudoku implementation, SudCell and Simple Sudoku Implementation ...

SudCell and Simple Sudoku Implementation We describe, fully, the SudCell class that will represent each of the 81 cells or boxes in a Sudoku puzzle.  Then we will

Zhtml requirements, In addition to your Java code requirements, you also ne...

In addition to your Java code requirements, you also need to enhance the ZHTML for your application. As before, you can continue working with the page(s) you used for the previous

Explain about the dynamic java, Dynamic JAVA Class and type informatio...

Dynamic JAVA Class and type information is kept around at runtime. This allows runtime loading and inspection of code in a very flexible way.

Gps and gprs fleet management system, GPS and GPRS fleet management system ...

GPS and GPRS fleet management system Project Description: I want to develop fleet management system Skills required: HTML, PHP, Java, Website Design

Program to insert item in tree, public class TreeTest {     public static v...

public class TreeTest {     public static void main(String args[])     {         Tree t = new Tree ();         System.out.println("Populating");         t.insertItem(1);         t

Expertise in gps or navigation app coding, Project Description: Two co-f...

Project Description: Two co-founders are in search of a developer to join us to launch a tech startup. We have experience at fortune 500 companies, elite consulting firms, etc.,

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