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, ...

An abstract class is a template definition of methods and variables in a specific class, or category of objects. In programming, objects are units of code, and each object is made into a generic class ...

Extension methods provide a great way for extending a class functionality -- but it's interfaces that let you use those methods anywhere you want. Extension methods let you add functionality to an ...

Nested classes are classes that are declared as members of other classes or scopes. Nesting classes is one way to better organize your code. For example, say you have a non-nested class (also known as ...