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

What would be the best way to share variables/objects between different GUI elements in java? Basically I have several ArrayList objects I want my modal dialogs to have access to. Also, where is ...

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.

Use Java assertions to test your assumptions about program correctness and check them in your code.