Classes, fields, methods, constructors, and objects are the building blocks of object-based Java applications. This Java tutorial teaches you how to declare classes, describe attributes via fields ...

What is the contract between equals() and hashcode()? Learn how these methods work together when comparing objects in Java.

Object-oriented systems are usually partitioned into layers of related responsibilities and only dependencies in one direction are allowed, from higher layers (more specific, less reusable) to lower ...

Java currently supports only two types of value: primitives and object references. Project Valhalla extends this by introducing inline classes which are a new form of type that exhibit some ...

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.

Last time, in ”Transitioning into object-oriented programming using Java,” we learned that for a programming language to be truly object-oriented, it should support information hiding ...