What is the use of private static method/variable?

Hi All,
I have read lots of books and tried lots of things but still not very clear on the
topic above.
When exactly do we HAVE to use private static methods?
private implies its only for class, cannot be accessed outside.
But then static means, it can be accessed giving classname.method.
They seem to be contradicting each other.
Any examples explaining the exact behaviour will be well appreciated.
Thanks,
Chandra Mohan

Static doesn't really "mean" that the method/field is intended for use outside the class - that is exactly what the access modifier is for.
Static implies that it is for use in relation to the class itself, as opposed to an instance of the class.
One good example of a private static method would be a utility method that is (only) invoked by other (possibly public) static methods; it is not required outside the class (indeed, it might be dangerous to expose the method) but it must be called from another static method so it, in turn, must be static.
Hope this helps.

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