Download Java Inheritance: Properties, Reasons and Examples and more Lecture notes Java Programming in PDF only on Docsity!
Inheritance in Java
Inheritance in Java is a mechanism in which one object acquires all the properties and behaviors of a parent object. It is an important part of OOPs (Object Oriented programming system).
The idea behind inheritance in Java is that you can create new classes that are built upon existing classes. When you inherit from an existing class, you can reuse methods and fields of the parent class. Moreover, you can add new methods and fields in your current class also.
Inheritance represents the IS-A relationship which is also known as a parent-child relationship.
Certi ed Salesforce Partner
Call Moderno Solutions Today
New Zealand Based Salesforce Experts. Get The
Reliable Advice From Our Experienced Staff.
moderno-solutions.com
OPEN
Why use inheritance in java
For Method Overriding (so runtime polymorphism can be achieved). For Code Reusability.
Terms used in Inheritance
Class: A class is a group of objects which have common properties. It is a template or blueprint from which objects are created. Sub Class/Child Class: Subclass is a class which inherits the other class. It is also called a derived class, extended class, or child class. Super Class/Parent Class: Superclass is the class from where a subclass inherits the features. It is also called a base class or a parent class. Reusability: As the name specifies, reusability is a mechanism which facilitates you to reuse the fields and methods of the existing class when you create a new class. You can use the same fields and methods already defined in the previous class.
The syntax of Java Inheritance
class Subclass-name extends Superclass-name { //methods and fields
Mercedes-Benz SLK Class 2007 for sale Visit Site
Mercedes-Benz SLK Class 2005 for sale Visit Site
Jaguar S Type 2005 for sale
Visit Site
The extends keyword indicates that you are making a new class that derives from an existing class. The meaning of "extends" is to increase the functionality.
In the terminology of Java, a class which is inherited is called a parent or superclass, and the new class is called child or subclass.
Java Inheritance Example
As displayed in the above figure, Programmer is the subclass and Employee is the superclass. The relationship between the two classes is Programmer IS-A Employee. It means that Programmer is a type of Employee.
class Employee{ float salary=40000; } class Programmer extends Employee{ int bonus=10000; public static void main(String args[]){ Programmer p=new Programmer(); System.out.println("Programmer salary is:"+p.salary); System.out.println("Bonus of Programmer is:"+p.bonus); } }
Certi ed Salesforce Partner
Call Moderno Solutions Today
New Zealand Based Salesforce Experts. Get The
Reliable Advice From Our Experienced Staff.
moderno-solutions.com
OPEN
File: TestInheritance.java
class Animal{ void eat(){System.out.println("eating...");} } class Dog extends Animal{ void bark(){System.out.println("barking...");} } class TestInheritance{ public static void main(String args[]){ Dog d=new Dog(); d.bark(); d.eat(); }}
Output:
barking... eating...
Multilevel Inheritance Example
File: TestInheritance2.java
class Animal{ void eat(){System.out.println("eating...");} } class Dog extends Animal{ void bark(){System.out.println("barking...");} } class BabyDog extends Dog{ void weep(){System.out.println("weeping...");} } class TestInheritance2{ public static void main(String args[]){ BabyDog d=new BabyDog(); d.weep(); d.bark(); d.eat(); }}
Output:
weeping... barking... eating...
Hierarchical Inheritance Example
File: TestInheritance3.java
class Animal{ void eat(){System.out.println("eating...");} } class Dog extends Animal{ void bark(){System.out.println("barking...");} } class Cat extends Animal{ void meow(){System.out.println("meowing...");} } class TestInheritance3{ public static void main(String args[]){ Cat c=new Cat(); c.meow(); c.eat(); //c.bark();//C.T.Error }}
Output:
meowing... eating...
Q) Why multiple inheritance is not supported in java?
To reduce the complexity and simplify the language, multiple inheritance is not supported in java.
Consider a scenario where A, B, and C are three classes. The C class inherits A and B classes. If A and B classes have the same method and you call it from child class object, there will be ambiguity to call the method of A or B class.
Since compile-time errors are better than runtime errors, Java renders compile-time error if you inherit 2 classes. So whether you have same method or different, there will be compile time error.
class A{
Certi ed Salesforce Partner
Call Moderno Solutions Today
New Zealand Based Salesforce Experts. Get The
Reliable Advice From Our Experienced Staff.
moderno-solutions.com
OPEN
Spring
Cloud Tutorial
Spring Clo.
Scipy
Tutorial
Scipy
DevOps
Tutorial
DevOps
GitHub
Tutorial
GitHub
Matlab
Tutorial
Matlab
Microservices
Tutorial
Microservices
Inkscape
Tutorial
Inkscape
Latex
Tutorial
Latex
Magento
Tutorial
Magento
Restful Web
Services
Tutorial
RESTful
Linq
Tutorial
LINQ
Laravel
Tutorial
Laravel
Aptitude
Aptitude
Logical
Reasoning
Reasoning
Verbal
Ability
Verbal A.
Interview
Questions
Interview
Company
Interview
Questions
Company
Artificial
Intelligence
Tutorial
AI
AWS
Tutorial
AWS
Selenium
tutorial
Selenium
Cloud
tutorial
Cloud
Hadoop
tutorial
Hadoop
ReactJS
Tutorial
ReactJS
Data Science
Tutorial
D. Science
Angular 7
Tutorial
Angular 7
Blockchain
Tutorial
Blockchain
Git Tutorial
Git
Machine
Learning
Tutorial
ML
Learn Latest Tutorials
Preparation
Trending Technologies
DBMS
tutorial
DBMS
Data
Structures
tutorial
DS
DAA
tutorial
DAA
Operating
System tutorial
OS
Computer
Network
tutorial
C. Network
Compiler
Design tutorial
Compiler D.
Computer
Organization
and
Architecture
COA
Discrete
Mathematics
Tutorial
D. Math.
Ethical
Hacking
Tutorial
E. Hacking
Computer
Graphics
Tutorial
C. Graphics
Software
Engineering
Tutorial
Software E.
html tutorial
Web Tech.
Cyber
Security
tutorial
Cyber Sec.
Automata
Tutorial
Automata
C Language
tutorial
C
C++ tutorial
C++
Java tutorial
Java
.Net
Framework
tutorial
.Net
Python
tutorial
Python
List of
Programs
Programs
Control
Systems
tutorial
Control S.
Data Mining
Tutorial
Data Mining
B.Tech / MCA
3Rm-$350 House Painting Hdb
Since 1985 we have remained one of singapore's top trusted painting company.
armstrongcoatingspecialist.com OPEN
