How to write a Singleton in proper manner?

Question

Today in my interview one interviewer asked me to write a Singleton class. And i gave my answer as

public class Singleton {

    private static Singleton re         


        

Answer 1

From What is an efficient way to implement a singleton pattern in Java?

Use an enum:

 public enum Foo 
 {
   INSTANCE;
 }

Joshua Bloch explained this approach in his book 'Effective Java'

Also check out The better Java singleton pattern nowadays?