Singleton Pattern

// ======== not thinking thread

class  Singleton
{
 private static Singleton singleton;
 private Singleton(){}
 public static Singleton getInstance()
 {
  if (singleton == null)
  {
   singleton = new Singleton();
  }
  return singleton;
 }
}

public class SingletonTest
{
 public static void main(String[] args)
 {
  Singleton singleton = Singleton.getInstance();
  Singleton singleton2 = Singleton.getInstance();
  System.out.println(singleton == singleton2);
 }
 
}