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Is it neccessary to have Mediator Singleton

Priyakant Charokar
Ranch Hand

Joined: May 08, 2004
Posts: 58

Hi all,
I would like to know "Is it the case that Mediator should be singleton??"


Thanks in Advance,


SCJP, SCWCD, SCMAD, SCEA, OCPJP 7, CSM
Frank Carver
Sheriff

Joined: Jan 07, 1999
Posts: 6920
Not at all.

A mediator is just a way of decoupling the objects in a group or collection from the the objects which manipulate them. It's quite feasible for an application to contain many mediator classes, and each class to be instantiated many times.

In the "Gang of Four" book ("Design Paterns", Gamma et al.) Mediator is discussed in the context of a dialog for selecting fonts. There is no reason for this or any other mediator to be a Singleton.

Why do you ask? Have you found a situation where you think a Mediator should be a Singleton?


Read about me at frankcarver.me ~ Raspberry Alpha Omega ~ Frank's Punchbarrel Blog
 
It is sorta covered in the JavaRanch Style Guide.
 
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