What is an interface?

The interface keyword takes the abstract concept one step further. You could think of it as a “pure” abstract class. It allows the creator to establish the form for a class: method names, argument lists, and return types, but no method bodies. An interface can also contain fields, but these are implicitly static and final. An interface provides only a form, but no implementation. An interface says, “This is what all classes that implement this particular interface will look like.”

December 5, 2008 | Filed Under Java