See the Java inheritance tutorial for a complete introduction to using the extends keyword and Object superclass in Java programs. See “Java tip: Inheritance relationships in JPA and Hibernate ...

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 ...

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 ...