java abstract class,concrete class and interface

what is the meaning of abstract class,concrete class and interface ?
1. In Java there is no multipliable inheritance like in C++ .But you can implement more thank one interface .
The interface methods are all abstract , this means contain no body ,and all properties are public static final (Means can't be changed later) . In interface you just say what is the class but don't say how to do it . Methods of interface are public and abstract by defaults and you don't need write the modifiers. interface can extend one or more interfaces .

Example

Code:

 interface shape 
{
         public abstract void   draw(); 

 }

Here a class circle implements the shape interface.

Code:

class shape implements shape
{
          public void draw()
                        {
                          // Draw body 
                         }


}  

 

2. Abstract class can have implemented methods and others not , you can't have an abstract method in non abstract class. you have always to remember to that abstract methods end with semicolon . example

Code:

public abstract class Vehicle {
private String type;
public abstract void goUpHill(); // Abstract method
public String getType() { // Non-abstract method
return type;
}
}
public abstract class Car extends Vehicle {
public abstract void goUpHill(); // Still abstract
public void doCarThings() {
// special car code goes here
}
}
public class Mini extends Car {
public void goUpHill() {
// Mini-specific going uphill code
}
}
 

Last edited by DrRakha on Fri May 31, 2013 12:59 pm, edited 3 times in total.

edit title

Author: Dummies In Java
Newbie

Posts: 4
Have thanks: 0 time

Page 1 of 1

[ 1 post ]

Related Posts to : java abstract class,concrete class and interface
The difference between an Interface and an Abstract class -
concrete class -
what is a concrete class -
What is an Abstract Class? !!! -
make abstract class -
how to Define abstract class in php -
why cant instantiate an abstract class -
Is garbageCollector a Class or interface? -
Define class helper class to check the method existance -
relationship between the Canvas class and the Graphics class -

Topic Tags

Java OOP

Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group
All copyrights reserved to codemiles.com 2007-2011
mileX v1.0 designed by codemiles team
Codemiles.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com