code: @Override
      public final PageFactory<? extends IRequestablePage> addingService(
              ServiceReference<PageFactory<? extends IRequestablePage>> reference) {
          PageFactory<? extends IRequestablePage> pageSource = super.addingService(reference);
          paxWicketPageFactory.add(pageSource);
          return pageSource;
      }
docs: {@inheritDoc}
  
  Default implementation of the
  {@code ServiceTrackerCustomizer.addingService} 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 returns the result of calling
  <code>getService</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 to customize the service
  object to be tracked for the service being added. In that case, take care
  not to rely on the default implementation of removedService that will
  unget the service.
  
  @see org.osgi.util.tracker.ServiceTrackerCustomizer