Do you need to know how to sort Java objects in a collection, array, or map? Here's how to use the Comparable and Comparator interfaces and avoid ClassCastExceptions. Programmers frequently need to ...

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, ...

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 ...

Community driven content discussing all aspects of software development from DevOps to design patterns. If you want to master functional programming, the best place to start is with the Java Function ...

The release of Java SE 15 in Sept 2020 will introduce "sealed classes" (JEP 360) as a preview feature. A sealed class is a class or interface which restricts which other classes or interfaces may ...