code: @Override
      public final void filterClose(NextFilter nextFilter, IoSession session)
              throws Exception {
          if (eventTypes.contains(IoEventType.CLOSE)) {
              IoFilterEvent event = new IoFilterEvent(nextFilter, IoEventType.CLOSE, session,
                  null); 
              fireEvent(event);
          } else {
              nextFilter.filterClose(session);
          }
      }
docs: {@inheritDoc}