i'm having some difficulties understanding when to use a static inner class
and when to use a non static inner class
lets say i'm implementing a LinkedList , and i want my nodes and my iterator
implemented in inner classes .
when and why should i declare them static or non static.
thank you very much in advance.
Inner classes are never static. Nested classes can be either static or non-static; a non-static nested class is called an inner class.
Anyway, an inner class implicitly gets a reference to an object of the outer class, while a static nested class doesn't, so the decision should depend on whether or not it needs that.
An iterator would need a reference to its collection so it would be a non-static nested class. A node wouldn't so it would be a static nested class.
When you are coding iterators or other interface implementations, the standard way is to use private inner (that is, non-static nested) classes, or even local classes and just return the class as the interface. That hides implementation details from the program that is using your linked list or widget.
