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.

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 ...

The first half of this introduction to Java inheritance teaches you how to use the extends keyword to derive a child class from a parent class, invoke parent class constructors and methods, and ...