Classes, Interfaces and Properties - Apex

Apex is an object-oriented programming language and this tutorial examines its support for these all important objects or class instances as they're sometimes called. Objects are created from classes—data structures that contains class methods, instance methods, and data variables. Classes, in turn, can implement an interface, which is simply a set of methods. Use the Developer Console to execute all of the examples in this tutorial.

Here is an overview of what this tutorial covers.

• Classes and Objects: Classes are templates from which you can create objects.
• Private Modifiers: The private modifier restricts access to a class, or a class method or member variable contained in a class, so that they aren’t available to other classes.
• Static Variables, Constants and Methods: Static variables, constants, and methods don’t depend on an instance of a class and can be accessed without creating an object from of a class.
• Interfaces: Interfaces are named sets of method signatures that don’t contain any implementation.
• Properties: Properties allow controlled read and write access to class member variables.