Question concerning interface functionality
I am quite new to Java, and I wonder how it is possible for an interface's methods to have empty bodies yet still be able to complete different tasks when invoked by classes. How can something undefined be functional?
The Runnable-interface, for example, only has one method, which has an empty body. How does that method receive its functionality, if it is not defined in the Runnable-interface? Does it receive the functionality from a class? In such a case, how do I assign functionality to an interface's methods? Thanks by advance.;)