Oracle says: "an interface is a group of related methods with empty bodies" I think of interfaces as a contract that a class promises the compiler to fulfill. If the ...

Interface in Java is actually easy to be understood but my very big question the very first time I encountered this: why use interface when you can define and declare methods in concrete classes? It ...

Java interfaces are different from classes, and it’s important to know how to use their special properties in your Java programs. This tutorial introduces the difference between classes and interfaces ...