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decorator design pattern

cherry hal
Greenhorn

Joined: May 06, 2012
Posts: 10
Hi,
Anybody can tell me about decorator designpattern
Punit Jain
Ranch Hand

Joined: Aug 20, 2011
Posts: 979
    
    2
To extend or modify the behaviour of ‘an instance’ at runtime decorator design pattern is used.
Inheritance is used to extend the abilities of ‘a class’.
Unlike inheritance, you can choose any single object of a class and modify its behaviour leaving the other instances unmodified.
i mean if you use inheritance and extend super class to sub class, then say, you created 100 objects of that class, your class functionality will be in all the 100 objects.
but you want that functionality in 2 or 3 objects that time you can decorate that object run time, that is where decorator pattern is used.
Winston Gutkowski
Bartender

Joined: Mar 17, 2011
Posts: 7484
    
  18

cherry hal wrote:Anybody can tell me about decorator designpattern

It'd be too much to put here, but this might help.

Otherwise: Do you have a specific question about the pattern? Or something particular that you don't understand?

Winston


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