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

Describe java operators, Describe java operators? An operator is a symb...

Describe java operators? An operator is a symbol which operates on one or more arguments to generate a result. The Hello World program is so easy it doesn't use any operators,

Change encrypted hsql database into csv format, Change encrypted HSQL datab...

Change encrypted HSQL database into CSV format Project Description: We have an encrypted HSQL Database which we have to convert into csv format. HSQL DB . We have java app

Program, Develop a code for fibonacci series

Develop a code for fibonacci series

What are commonsense guidelines to prevent viruses, What are Commonsense Gu...

What are Commonsense Guidelines to prevent viruses? Discuss about Antivirus as well. Commonsense Guidelines to avoid viruses are as follows: 1. Do not open attachment of unwant

Programming, write a Java program that accept two integers and determine we...

write a Java program that accept two integers and determine weather they are Coprime or not

Difference between java mail and jms queue, JMS is the ideal high-performan...

JMS is the ideal high-performance messaging stage for intra business messaging, with full programmatic control over quality of service and delivery options. JavaMail gives lowes

What does the keyword "synchronize" mean in java, What does the keyword " s...

What does the keyword " synchronize " mean in java. What are the usage and disadvantages of synchronization?

Write a program on filling rectangles, Write a program on Filling Rectangle...

Write a program on Filling Rectangles ? The drawRect() method draws an open rectangle, a box if you prefer. If you need to draw a filled rectangle, use the fillRect() method. O

Loops, #questiongfjnkdfn..

#questiongfjnkdfn..

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