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
posted 9 years ago
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?