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Using a Observer Pattern in a Application .

PavanPL KalyanK
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Joined: Feb 28, 2009
Posts: 212
"Simply, the Observer pattern allows one object (the observer) to watch another (the subject)."

Can anybody please in what cases we need to Observe an Object ?

My question is what is the need to use an Observer Pattern?

Thanks in advance.
Saifuddin Merchant
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Joined: Feb 08, 2009
Posts: 606

Typically the Observer pattern would be used in a Publisher-Subscriber situation. The observer pattern allows you to reduce coupling between the subscriber and publisher by reducing the knowledge each class must have about the other.
The publisher (subject) exposes a method by which subscribers (object) can register/de-register with it. This allows the publisher to maintain a list of subscribers without actually knowing their implementation - This is just a gist...

You can read more here.


Cheers - Sam.
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PavanPL KalyanK
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Joined: Feb 28, 2009
Posts: 212
Thanks sam , it was a good answer.
 
I agree. Here's the link: http://aspose.com/file-tools
 
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