Is class a singleton or not . how to make a class as a singleton or a prototype

Is class a singleton or not . how to make a class as a singleton or a
prototype

By default a class is singleton or not ..
public class You{
}



public class My(){
public static void main(String a[]){
You you=new You();
}
}
is you object is singleton .. if it is singleton how to make it prototype
.. if it is prototype how to make a class as singleton..
Thank you in advance..