Singleton pattern with combination of lazy loading and thread safety

Question

I was doing some research about singletons, specifically regarding lazy vs eager initialization of singletons.

An example of eager initialization:

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Answer 1

You first design is actually lazy. Think about it, the instance is only created when the class is initialized; the class is only initialized when the getSingleton() method is called [1]. So the instance is only created when it's asked for, i.e. it's lazily created.

[1] http://docs.oracle.com/javase/specs/jls/se7/html/jls-12.html#jls-12.4.1