code: public void fireEvent(final InvalidationEvent event) {
          if (bUpdateInvalidationListener) {
              synchronized (hsInvalidationListeners) {
                  if (invalidationListenerCount > 0) {
                      currentInvalidationListeners = new InvalidationListener[invalidationListenerCount];
                      hsInvalidationListeners.toArray(currentInvalidationListeners);
                  } else {
                      currentInvalidationListeners = EMPTY_INV_LISTENERS;
                  }
                  bUpdateInvalidationListener = false;
              }
          }
          try {
          	event.m_cacheName = this.cacheNameNonPrefixed;
  			for (int i = 0; i < currentInvalidationListeners.length; i++) {
  				final InvalidationListener currentIL = currentInvalidationListeners[i];
  				if (_async) {
  					Scheduler.submit(new Runnable() {
  						@Override
  						public void run() {
  							currentIL.fireEvent(event);
  						}
  					});
  				} else {
  					currentIL.fireEvent(event);
  				}
  			}
          }
          catch (Throwable t) {
          	com.ibm.ws.ffdc.FFDCFilter.processException(t, "com.ibm.ws.cache.DCEventSource.fireEvent", "85", this);
          	if (tc.isDebugEnabled()) {
          		Tr.debug(tc, "Exception thrown in fireEvent method of InvalidationListener\n" + t.toString());
          	}
          }
      }
docs: The listeners are called when the fireEvent method is invoked.
  @param event The invalidation event to be fired.