OOPS - What is the need of an abstract class?

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What is the need of an abstract class?

If I write all of concrete methods in one class and all abstract methods in an interface and extend and implement both in third class assume that third class don't extend any other class?

Total Answers and Comments: 4

Last Update: August 16, 2008 Asked by: Chandrashekhar

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Submitted by: ramesh.sukka

Providing the Abstract functionality to object is one of the powerful concepts by java, I will give you one sample scenarios where you required implement the abstract class,

Assume that you are going to design TV remote (in real time it will be your client business) with 100 new functionalities in it but you know only 30 functionalities to implementation at this moment. So you will provide implementation for 30 method and rest of 70 methods are abstract. When ever new class extends it, it should be implement rest of 70 methods.

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shilpad

October 23, 2007 08:57:33

sarithahere528

Member Since: October 2007 Contribution: 10

RE: What is the need of an abstract class?

U need to implement all the methods of interface and if u want u can override methods of extended class ...

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November 17, 2007 16:12:58

ramesh.sukka

Member Since: November 2007 Contribution: 7

RE: What is the need of an abstract class?

Providing the Abstract functionality to object is one of the powerful concepts by java, I will give you one sample scenarios where you required implement the abstract class,

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Overall Rating: +1

February 13, 2008 04:20:50

sampra

Member Since: February 2008 Contribution: 279

RE: What is the need of an abstract class?

If we have some method which body is not defined till declartion of class and body is implemented in subclass later then declare that class as abstract class.If a class has atlest one abstract method then we have to declare class as abstract class

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August 15, 2008 12:02:07

alkumar2000

Member Since: August 2008 Contribution: 5

RE: What is the need of an abstract class?

Abstract is most useful when you are creating a framework..take the example of template method pattern which is used in the templates provided by spring framework for the support of jdbc or hibernate it absrtacts out all the common things which needs to be done in the templates that it provides the only thing now the developer has to do is to extend these classes create and execute the query.The develepor here doesn't need to worry to get the connection and close the connection.

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