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 ...

Java lets you declare interfaces inside of classes. Once declared, an interface is automatically a static member of the class. There is no need to declare the interface with the static keyword.

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.