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.

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

If you want to take advantage of sorting methods in Java, you'll need to implement the Comparable interface.

Traditional Java 8 Predicate example While the Java 8 Predicate is a functional interface, there's nothing to stop a developer from using it in a traditional manner. Here's a Java Predicate example ...