The Java Tutorial goes on to list bullets for when an abstract class should be considered and for when an interface should be considered. Unsurprisingly, these are derived from the previously ...

Java also lets you nest interfaces in interfaces and classes in interfaces. Check out this article on nested interfaces to learn about this strange but occasionally useful Java language feature.

The functional Predicate interface gets used extensively by the Java 8 Streams API. Any developer who wants to master functional programming in Java will need to be comfortable with the Predicate ...

Sealed classes in Java let developers limit the creation and use of subclasses and preserve the class hierarchy. Here is how sealed classes in Java work.