code: public static PaxWicketInjector getInjector() {
          String applicationName = Application.get().getApplicationKey();
          PaxWicketInjector injector = null;
          synchronized (instance.injectorMap) {
              injector = instance.injectorMap.get(applicationName);
          }
          if (injector == null) {
              throw new IllegalStateException(String.format("No Injector is set for application %s",
                  Application.get().getApplicationKey()));
          }
          return injector;
      }
docs: Retrieves the InjectionHolder responsible for the active {@link org.apache.wicket.Application}. Therefore this will only work in an
  active Wicket context!
  
  @return Injector