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Inner Classes

Vineela Devi
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Joined: Dec 20, 2003
Posts: 191
Hi,

Can anyone tell what is the use /advantages of having Inner classes.Tell me a real world scenraio when we may need them.

Regards,
Vineela
Jeff Albertson
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Joined: Sep 16, 2005
Posts: 1780
Common use: as event listener classes in Swing GUIs.

Advantage: listeners are often small classes that know implementation details of their enclosing classes. This is a good match for nested classes.

Disadvantage: code reuse. But when you realize a listener can be turned into a useful top-level class (for example the Action behind the exit menu item), you refactor. Most of the time event listeners are too specific for you to consider reuse.


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Jan Groth
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Joined: Feb 03, 2004
Posts: 456
creating a class that implements the Comperator interface can be done on the fly as a anonymous inner class. that can be by far the easiest solution if you need to pass a Comperator into a method call, even though i go with poster #1 - the code is not so reusable...

jan
 
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