What is the use of an abstact class?

Hi friends,
why we need to the abstract class...in which scenario????????
Thanks

ghostbust555 wrote:
THe abstract class is very useful because you can force people who extend a class to override a method.That does not do anything to explain the use of an abstract class.
For example when I was creating JavaPoint (sourceforge.net/projects/javapoint) I created an object called GraphicObject. It cotained code for different things related to drawing images and shapes on the screen. But the method to convert each GraphicObject to XML for saving was made abstract because each different type of GraphicObject (CircleGraphicObject, SquareGraphicObject ...) needed different code to turn it into XML. Thats just one example there are many many uses for it though.That almost kinda sorta explains the user of abstract classes.
@OP: The use of an abstract class is when you 1) want to define a type--that is, what some particular type can do, 2) want to allow different, independent implementations of that type, and 3) want to provide a reasonable default implementation for some of that type's operations.

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