code: public synchronized void addSingletonInitialization(EJSHome home) {
          if (ivStopping) {
              throw new EJBStoppedException(home.getJ2EEName().toString());
          }
  
          if (ivSingletonInitializations == null) {
              ivSingletonInitializations = new LinkedHashSet<EJSHome>();
          }
          ivSingletonInitializations.add(home);
      }
docs: Record the initialization attempt of a singleton. This method must not be called for
  a bean before it is called for each of that bean's dependencies. This method may be
  called multiple times for the same bean, but only the first call will have an effect.
  
  @param home
  the bean's home
  @throws EJBStoppedException
  if the application is stopping