code: @Override
      public void close() {
          // Not connected, but close the underlying AHC.
          if (transportInUse == null) {
              closeRuntime(false);
          } else if (socketRuntime != null && !transportInUse.status().equals(STATUS.CLOSE)) {
              transportInUse.close();
              closeRuntime(true);
          }
      }
docs: {@inheritDoc}