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 ...

Create packages, import packaged classes and interfaces into your programs, move packages, and encapsulate them in jar files.

Here’s an example of how a Function and lambda expression work together: Function<Integer, String> verboseLambda = (Integer x)-> { return Integer. toString (x*x); }; System.

Do you need an example of how to use Java's UnaryOperator in a functional Lambda expression? This tutorial shows you where when and how to use the UnaryOperator interface in a function.