Inheritance and composition are two programming techniques developers use to establish the relationship between classes and objects. Whereas inheritance derives one class from another, composition ...

In Java 101: Inheritance in Java, Part 1, you learned how to leverage inheritance for code reuse, by establishing is-a relationships between classes. Composition is a closely related programming ...

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 ...