/**
  * This method is called when a used handler factory disappears. This method is synchronized to
  * avoid concurrent calls to method modifying the factory state.
  *
  * @param reference the leaving service reference.
  * @param service the handler factory object.
  * @see
  *     org.apache.felix.ipojo.util.TrackerCustomizer#removedService(org.osgi.framework.ServiceReference,
  *     java.lang.Object)
  */
 public synchronized void removedService(ServiceReference reference, Object service) {
   // Look for the implied reference and invalid the handler identifier
   for (Object m_requiredHandler : m_requiredHandlers) {
     RequiredHandler req = (RequiredHandler) m_requiredHandler;
     if (reference.equals(req.getReference())) {
       req.unRef(); // This method will unget the service.
       computeFactoryState();
       return; // The factory can be used only once.
     }
   }
 }