Answer Posted / zafar

No, you cannot create an instance of an interface. An
interface has no implementation - a class that implements
the interface specifies the implementation.

However, you can ofcourse have a reference variable of an
interface type that points to an instance of a class that
implements the interface. For example:

// List is an interface, ArrayList implements interface List
List data = new ArrayList();


It's good practice to program like this - program to an
interface, not an implementation. If you want to know more
about that design principle, see, for example:
[url=http://www.artima.com/lejava/articles/designprinciples.
html]Design Principles from Design Patterns[/url]

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