Singleton class in Java

This “Singleton class in Java” page is explaining rules to create user defined singleton class and how to work with singleton class in java application.

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Singleton class:

  • Class must be public
  • Properties must be private
  • It is not allowed to instantiate the class directly(contains private constructor).
  • Using Factory method, we can get instance of this class.
  • “Factory method” is a static method available in Singleton-class.
  • “Factory method” creates an object and returns from its definition.

 

Note: The only difference between Factory class and Singleton class is, “Factory class” can be instantiated many times where as “Singleton” class only once.

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