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 ...

This makes the code more efficient. The metaphor that is often used here, is to say that classes in Java are the “blueprints” whereas the objects are single examples of that product.

While there are workarounds -- for example, you could introduce a Factory class to generate transaction objects -- this adds complexity and could become a maintenance burden. Another approach could be ...

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.

Java currently supports only primitive types and object references. Project Valhalla extends this by introducing inline classes which are new types that exhibit some behaviors of both types of value.

Dynamic loading of Java classes at runtime provides tremendous flexibility in the development of enterprise systems. It provides for the basis of "application servers", and allows even simpler, ...

For more on that, check out our guide to Android development for beginners. For the purposes of this Java tutorial, it may be easier to write your code directly into a Java compiler app.