Singleton Pattern

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Video

https://www.youtube.com/watch?v=hUE_j6q0LTQ

Definition

Singleton pattern is a software design pattern that restricts the instantiation of a class to one. This is useful when exactly one object is needed to coordinate actions across the system. The term comes from the mathematical concept of a singleton.

Usage

Singleton design pattern.png

 class Singleton {
   static private Singleton Instance
   private Singleton(){}

   public static Singleton getInstance(){
      if(Instance == null){
          Instance = new Singleton()
      }
      return Instance
   }
 }
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