Understanding early Instantiation of Singleton Pattern

Static factory method: This provides the global point of access to the Singleton object and returns the instance to the caller.

Private constructor: It will prevent to instantiate the Singleton class from outside the class.

Static member: It gets memory only once because of static, itcontains the instance of the Singleton class.

To create the singleton class, we need to have static member of class, private constructor and static factory method. It is used in logging, caching, thread pools, configuration settings etc. Singleton pattern is mostly used in multi-threaded and database applications.Only single instance is reused again and again. Saves memory because object is not created at each request.Lazy Instantiation: creation of instance when required.Early Instantiation: creation of instance at load time.There are two forms of singleton design pattern

In other words, a class must ensure that only single instance should be created and single object can be used by all other classes. Singleton Pattern says that just 'define a class that has only one instance and provides a global point of access to it'.

Serializable kotlin data class