In this Java 101 tutorial, I’ve explained how interfaces differ from classes, and showed you how to declare, implement, and extend interfaces in your Java programs.

Learn about serialization in Java with our comprehensive tutorial. We provide examples to help you understand how serialization works. ... Java provides the Externalizable interface.

There are over 40 functional interfaces listed in the java.util.functions package, which can make the prospect of functional programming in Java ... This restriction doesn’t apply to the Function ...

So to learn Java lambda syntax, you need to be familiar with its three component parts: The argument list; The arrow; The method body; To apply these concepts, we first need a functional interface. A ...

For an introduction to Java interfaces, including the difference between classes and interfaces, see my Java 101 tutorial Working with interfaces in Java. Nesting interfaces in classes.