Interface – Interface is the blueprint of class, specifying what a class should do. The interface in Java refers to an abstract “class” that is used to group related methods with “empty ...

The Java 2 SDK organizes its vast collection of classes and interfaces into a tree-like hierarchy of packages within packages, which is equivalent to directories within directories.

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.

Sealed classes make Java an even more powerful and expressive language and set the stage for even more sophisticated techniques such as pattern matching, which we'll explore in a subsequent article. A ...