code: @Override
      public final void removedService(ServiceReference<PageFactory<? extends IRequestablePage>> reference,
              PageFactory<? extends IRequestablePage> service) {
          if (LOGGER.isDebugEnabled()) {
              LOGGER.debug("removedService( " + reference + ", " + service + ");");
          }
          paxWicketPageFactory.remove(service);
          super.removedService(reference, service);
      }
docs: {@inheritDoc}
  
  Default implementation of the
  <code>ServiceTrackerCustomizer.removedService</code> method.
  
  <p>
  This method is only called when this <code>ServiceTracker</code> object
  has been constructed with a <code>null ServiceTrackerCustomizer</code>
  argument.
  
  The default implementation calls <code>ungetService</code>, on the
  <code>BundleContext</code> object with which this
  <code>ServiceTracker</code> object was created, passing the specified
  <code>ServiceReference</code> object.
  <p>
  This method can be overridden in a subclass. If the default
  implementation of <code>addingService</code> method was used, this method
  must unget the service.
  
  @see org.osgi.util.tracker.ServiceTrackerCustomizer