Design Pattern: Singleton

The singleton design pattern is one of a kind, The singleton is a creational pattern that makes sure you only have one instance of a class, while providing global access to this object.

Requirements:

• Must use a private constructor preventing new instantiations of this class
• a static method that acts like a constructor, “getInstance()” that returns the same instance of your singleton class or if no instance exist returns a new one.

UML Diagram example