Why Enum Singleton are better in Java

1) Enum Singletons are easy to write
public enum EasySingleton{
    INSTANCE;
}
2) Enum Singletons handled Serialization by themselves
Another problem with conventional Singletons are that once you implement serializable interface they are no longer remain Singleton because readObject() method always return a new instance just like constructor in Java. you can avoid that by using readResolve() method and discarding newly created instance by replacing with Singeton as shwon in below example :

    //readResolve to prevent another instance of Singleton
    private Object readResolve(){
        return INSTANCE;
    }

Java Enum's  
private void readObject(ObjectInputStream in) throws IOException,
      ClassNotFoundException {
      throw new InvalidObjectException("can't deserialize enum");
}

Enum singleton are perfect as soon as you don't need a singleton that inherit from something. In that case, you cannot use enum anymore and you must use other way...

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