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 ...

The release of Java SE 15 in Sept 2020 will introduce "sealed classes" (JEP 360) as a preview feature. A sealed class is a class or interface which restricts which other classes or interfaces may ...

Classes and objects in Java must be initialized before they are used. You’ve previously learned that class fields are initialized to default values when classes are loaded, and that objects are ...