In “Events and Listeners,” I outlined a generic recipe for creating and firing custom events. Since the original answer published, I’ve received several emails requesting a complete, concrete example.

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 ...

A great deal of Java programming -- from conditional statements to iterative loops -- deals with the evaluation of true or false values. When you work with the JDK's Streams API and Lambda functions, ...