Example of Java Singleton

public class SimpleSingleton {

    private static SimpleSingleton singleInstance =  new SimpleSingleton();

    //Marking default constructor private

    //to avoid direct instantiation.

    private SimpleSingleton() {

    }

    //Get instance for class SimpleSingleton

    public static SimpleSingleton getInstance() {

        return singleInstance;

    }

 

 

or

public enum SimpleSingleton {

    INSTANCE;

    public void doSomething() {

    }

}

 

//Call the method from Singleton:

SimpleSingleton.INSTANCE.doSomething();