Compare inheritance and composition, the two fundamental ways to relate Java classes, then practice debugging ClassCastExceptions in Java inheritance.

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 in Java let developers limit the creation and use of subclasses and preserve the class hierarchy. Here is how sealed classes in Java work.

It's not good enough to simply use inheritance and apply the rules of polymorphism to your code. To write SOLID code, and properly implement the Liskov substitution principle in Java, your code must ...

I favor composition as a general rule, but private inheritance and composition are essentially the same thing. I've occasionally found it useful to privately inherit from standard containers ...