Writing an Interface3:57 with Alena Holligan
Interfaces allow us to talk about requirements without the need for implementation details. In other words, what do we need to be able to do with this object? This will help with both building a class and implementing an object.
Documentation for Object Interfaces
Object interfaces allow you to create code which specifies which methods a class must implement, without having to define how these methods are handled.
Interfaces are defined in the same way as a class, but with the interface keyword replacing the class keyword and without any of the methods having their contents defined.
All methods declared in an interface must be public; this is the nature of an interface.
To implement an interface, the implements operator is used. All methods in the interface must be implemented within a class; failure to do so will result in a fatal error. Classes may implement more than one interface if desired by separating each interface with a comma.
Constants: It's possible for interfaces to have constants. Interface constants works exactly like class constants except they cannot be overridden by a class/interface that inherits them.
You need to sign up for Treehouse in order to download course files.Sign up