This post explains how to use classes in Java to build objects and organize your code. Also learn: constructors, static methods, and more!

Abstract classes and interfaces in Java serve fundamentally different purposes. Learn the differences between these Java language elements and how to use them in your programs.

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.

Typesafe enums offer a better alternative to Java's traditional enumerated types. Here's how to use typesafe enums correctly in your Java code.

Java collection classes allow a developer to keep track of contained items in one of two ways, either by an indexed count or a key. This creates an obvious limitation where multiple values can’t be ...