code: @Override
      public boolean enableListener(boolean enable) {
          boolean success = super.enableListener(enable);
          this.coreCache.setEventSource(eventSource);
          return success;
      }
docs: enableListener - enable or disable the invalidation, change and preInvalidation listener support.
  You must call enableListener(true) before calling addInvalidationListner(), addChangeListener() or
  addPreInvalidationListener(). The EventSource is passed to the CoreCache so that it can fire events.
  
  @param enable - true to enable support for invalidation, change and preInvalidation listeners
  or false to disable support for invalidation, change and preInvalidation listeners
  @return boolean "true" means listener support was successfully enabled or disabled.
  "false" means this cache is configurated to use the listener's J2EE context for
  event notification and the callback registration failed. In this case, the caller's thread
  context will be used for event notification.