Originally Posted by
javapenguin
Calendar isn't a Singleton?! Then why does it have a getInstance() method?
What is the Runtime class for? It does indeed appear to be a Singleton.
Calendar's constructor is protected, so maybe it isn't a Singleton, but it appears to be nearly a Singleton, as you can't access the constructor directly (unless you subclass Calendar.).
Having a getInstance() method and/or a private/protected constructor does not define a Singleton - it is defined just as Norm has defined it: there exists one instance in an application.