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.

See the Java 101 Java interfaces tutorial for a more in-depth introduction to using interfaces in your Java programs, including where and where not to use default, static, and private methods.

A public method should never be called by another public method within the same class hierarchy. It should only be called by other classes via the classes' public interface. Class calls might not be ...

If you want to take advantage of sorting methods in Java, you'll need to implement the Comparable interface. Written by David Petersheim, Contributor Feb. 17, 2005, 8:00 a.m. PT ...

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 ...