Learn the difference between classes and interfaces once and for all, then get started declaring, implementing, and extending interfaces in your Java programs ...

Why does Java's standard class library contain empty interfaces like Cloneable and Serializable? Find out why in this sixth installment in the "Object-oriented language basics" series. You'll also ...

We have just learned how to create and implement interfaces as well as how to create and extend abstract classes so now let's practice a bit.

The key difference, however, is that when the Predicate interface runs, a true or false value must be returned. Here is a lambda expression and Predicate example: Predicate<Integer> lambdaPredicate = ...

The functional consumer interface is a key part of the Java Streams API. Here is a simple Consumer interface example to show you how to use this Java component.