code: public void shutdown ()
      {
          log.info("Client manager shutting down", "ccount", _usermap.size());
  
          // inform all of our clients that they are being shut down
          synchronized (_usermap) {
              for (PresentsSession pc : _usermap.values()) {
                  try {
                      pc.shutdown();
                  } catch (Exception e) {
                      log.warning("Client choked in shutdown()",
                                  "client", StringUtil.safeToString(pc), e);
                  }
              }
          }
      }
docs: from interface Lifecycle.Component