JAVA the Singleton Class Implemantation or Singleton pattern

package com.mastermoin.java;

public class SingletonClass {

       private SingletonClass(){}

      

       private static SingletonClass object = null;

      

       public static SingletonClass getInstance(){

              if(object==null){

                     object = new SingletonClass();

              }

              return object;

       }

      

}

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How to use 

package com.mastermoin.java;

public class DemoRun {

       public static void main(String[] args) {

              SingletonClass object = SingletonClass.getInstance();

       }

}

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