Why does Java provide both abstract class as well as interface

Home Answers Viewqa Java-Interview-Questions Why does Java provide both abstract class as well as interface

Anil

Why does Java provide both abstract class as well as interface
2 Answer(s) 2 years and 4 months ago
Posted in : Java Interview Questions

why does java have both abstract class as well as interface? what is the need or importance of having both?

View Answers

January 7, 2011 at 5:40 PM

Hi Friend,

They both have some unique features.

An interface is used in situations when a class needs to extend an other class apart from the abstract class. In such situations it is not possible to have multiple inheritance of classes. An interface on the other hand can be used when it is required to implement one or more interfaces. Abstract class does not support Multiple Inheritance whereas an Interface supports multiple Inheritance.

Abstract classes are used when you do intend to create a concrete class, but want to make sure that there is some common state in all the subclasses or a possible common implementation for some operations. Interfaces cannot contain either.

Thanks

October 8, 2012 at 10:13 PM

we use interface in case of multiple inheritance. if an interface contains 100 methods and we want to implements its only two or three methods at that time we make an abstract class and implements that interface in that class and we are able to use only required methods or our needs

Why does Java provide both abstract class as well as interface
Why does Java provide both abstract class as well as interface why does java have both abstract class as well as interface? what is the need or importance of having both

abstract class and interface - Java Beginners
() { System.out.println ("Moo! Moo!"); } } Why not declare an abstract class as an interface...? when should we use an abstract class? when should we use interface instead of abstract class? Hi friend, Abstract classes In java

Abstract and Interface
Interface and Abstract Class 1)Main difference is methods of a Java interface... declared in a Java interface is by default final. An abstract class may contain non... extend another Java interface only, an abstract class can extend another Java

Uses of abstract class & interface - Java Beginners
to java. I knew the basic concepts of interface and the abstract class. But i dont... my doubt Thank you Hi Friend, Interface: Java does... that extends the abstract class has to provide the implementation to the abstract

why we use abstract class in java?
why we use abstract class in java? what is the the purpose of abstract class.Give example when to use abstract and when use interface

Interface Vs Abstract Class
Interface Vs Abstract Class ..., an interface is equivalent to a fully abstract class (a class with only public abstract... need to use an abstract class, because they provide more design flexibility

Marker Interface,Java Marker Interface
; and "Why use Marker Interface?" and "difference between abstract... Interface Abstract Class.... Abstract classes may contain both instance as well as static variables

Abstract class and interface in Java
Abstract class and interface in Java What is the difference between abstract class and interfaces in Java? Differences between an interface and an abstract class: At the same time multiple interfaces can

Interface and Abstract class
Interface and Abstract class hello,, Can some body tell me what is the difference between an Interface and an Abstract class? hi, Very... public members whereas an abstract class can contain private as well as protected

Interface and Abstract class
and Abstract Class 1)Main difference is methods of a Java interface are implicitly...)Members of a Java interface are public by default. A Java abstract class can have... interface should be implemented using keyword 'implements'; A Java abstract class should

Interface
for Interface in java? and want to know why they used interface instead of multiple inheritance? Thanks in advance An interface is one which has abstract... and implements its methods (which are declared in interface) int the class. interface Ex

Interface in Java
; and "Why to use Marker Interface?" and "difference between abstract...; Features Interface Abstract Class... and static. Abstract classes may contain both instance as well as static

Abstract class and Interface - Java Magazine
Abstract class and Interface Dear Sir, Please anyone help me........I wane exact difference between Abstract class and Interface.what... abstract class AbstractExample { public AbstractExample(){ System.out.println

abstract class
abstract class what is abstract class .why we use it or what is the need of this class? Abstract class is like base class which... the following links: http://www.roseindia.net/help/java/a/java-abstract-class.shtml

Why Abstract Class?
Why Abstract Class? What is the use of Abstract Class if it has Zero Abstract methods

abstract class and overriding - Java Beginners
abstract class and overriding? Interface? Give some example program? Hi friend, Abstract class : In java programming language, abstract classes..._value(); } } Difference between abstract class and interface

Interface vs abstract class
Interface vs abstract class Hai, Is there any possible to defining abstract methods in Interface

Java Abstract Class
Java Abstract Class An abstract class is a class that is declared by using the abstract keyword...; --or-- Java provides a special type of class called an abstract class

Java Abstract Class Example
Java Abstract Class Example In this section we will read about the Abstract class. Abstract class in Java is a class which is created for abstracting the behaviour of classes from the outside environment. Abstract class can be created

Abstract class - Java Beginners
Abstract class Why can use abstract class in java.?when abstract class use in java.plz Explain with program. abstract class abs{ public void display(){ } public abstract void display1(); } public class win

Using Abstract Class
Using Abstract Class We does not make a object of the abstract class. This class must be inherited. Unlike interface the abstract class may

Abstract class,Abstract methods and classes
(); Abstract Class In java programming language, abstract classes... so many times the word abstract. In java programming language the word abstract... that have the empty implementation. All the methods in any interface are abstract

The abstract Keyword : Java Glossary
the methods without implementations. Abstract class in java have abstract.... In java program abstract class is deliberately missing similar to like an interface which will missing all method bodies in the program. Abstract class

What is Abstract classes in Java?
. That's why the Abstract class in Java programming language is used to provide...What is Abstract classes in Java? What is Abstrack class in Java... visit Abstract class in Java

Java Inheritance and abstract - Java Interview Questions
abstract class or interface. Because both provides the abstract method. Thank...Java Inheritance and abstract 1) Why we need to write the separate Interface in which we are not doing any operation except declaring empty abstract

Class or Interface
Java NotesClass or Interface Declare variables as class or interface type.... Why change the underlying class? The two List classes, ArrayList and LinkedList both implement the same List interface methods and can be manipulated

Interfaces and Abstract Classes - Development process
Interface and Abstract Classes? Hi Friend, Interface: Java does.... It relate classes from different types of hierarchy. Abstract Class: Any class that extends the abstract class has to provide the implementation to the abstract

Real Time Example Interface and Abstract Class - Java Beginners
Real Time Example Interface and Abstract Class Hi Friends, can u give me Real Time example for interface and abstract class.(With Banking Example

Abstract Class in Java
Abstract class in Java is a class that is declared using abstract keyword. It cannot be instantiated but can be extended into subclass. Abstract class cannot... abstract as well. All abstract methods must be public. When an abstract class

Abstract Classes - Java Interview Questions
Abstract Classes Why we cann't instantiate a Abstract Classes? Even if an Abstract Class does not have any abstract methods, but declaring the class as abstract prevents it from creating an instance. Why? Thanks in Advance

abstract class
abstract class Explain the concept of abstract class and it?s use with a sample program. Java Abstract Class An abstract class is a class that is declared by using the abstract keyword. It may or may not have

Interface in java with example
We are going to discuss about Interface in Java. Interface is blueprint of a class. Interface is a collection of abstract methods. Interface has only... extending interface. Why use interface in java? We use itto achieve complete

Abstract class
Abstract class j An Abstract class is a base class which...://www.roseindia.net/help/java/a/java-abstract-class.shtml http://www.roseindia.net/java/master-java/abstract-class.shtml

interface
interface what the use of interface? An interface is one which has abstract methods(not defined just declared)and static or non static variables.Any class can implement(inherit)the interface and make use

interface
; Through interface, we can achieve the multiple inheritance. Java does... it will take.It creates complexity.Therefore java does not support it directly...interface What is the exact use of interface in real time scenario

Java Interface
class. It is saved with the .java extension. Inside an interface we can't... Java Interface In this section we will discuss about the interface in Java... extends the other interface. 3. How a class can implement one or more than one

What are the difference between abstract class and interface?
What are the difference between abstract class and interface? What are the difference between abstract class and interface

why java does not support multiple inheritance - Java Beginners
why java does not support multiple inheritance hello friend, i... then why we can not extends multiple classes in a single class, eventhough...().show1(1,2); new A4().show1(3); } } Hi Friend, Java does

Java abstract class
Java abstract class Can an abstract class be final

Interface in JSP
the methods are abstract. There is no code associated with an interface. In an interface all the instance methods are public and abstract. Interfaces are always implemented in the class. They provide extra behaviors to the class

Why does Java not support operator overloading?
Why does Java not support operator overloading? Hi, Why does Java not support operator overloading? thanks

abstract class - Java Beginners
abstract class what exactly is abstract class and in which cases its..., In java programming language, abstract classes are those that works only... inherited from the abstract class (base class). Abstract classes

EJB, Enterprise java bean- Why EJB (Enterprise Java Beans)?
Why EJB (Enterprise Java Beans)? Enterprise Java Beans or EJB for short is the server-side component architecture for the Java 2 Platform

where exactly we use interface and where abstract class?
where exactly we use interface and where abstract class? what is the use of interface over abstract class? and where we should use interface and where abstract class

Abstract and Interface
Abstract and Interface what is the difference between Abstract and Interface accurateatly

Interface - Java Interview Questions
Interface Respected sir why we use Interface in java? because we have abstract class for do same work. Hi Anwer, When you define... can still mark the class as abstract. Developing by interface helps in object

abstract class - Java Interview Questions
abstract class Explain the abstract class and abstract method...://www.roseindia.net/java/master-java/abstract-class.shtml http://www.roseindia.net/help/java/a/java-abstract-class.shtml Hope that it will be helpful for you. Thanks

The interface keyword
to implement an interface by a class. Interfaces in java are abstract means they can.... An interface in java includes only abstract methods i.e. methods have signatures...). An abstract type in java defines that it must be implemented by any class to make

Java-Abstract Class - Java Beginners
Java-Abstract Class Can a abstract class have a constructor ?When would the constructor in the abstract class be called ? Please give me with good...; Hi Friend, Yes. But Abstract class constructors will be called when its

Ask Questions?

If you are facing any programming issue, such as compilation errors or not able to find the code you are looking for.

Ask your questions, our development team will try to give answers to your questions.

Tutorial Topics