code: protected void register(IConnection conn) {
          if (log.isDebugEnabled()) {
              if (conn == null) {
                  log.debug("Register null connection, client id: {}", id);
              } else {
                  log.debug("Register connection ({}:{}) client id: {}", conn.getRemoteAddress(), conn.getRemotePort(), id);
              }
          }
          if (conn != null) {
              IScope scope = conn.getScope();
              if (scope != null) {
                  log.debug("Registering for scope: {}", scope);
                  connections.add(conn);
              } else {
                  log.warn("Clients scope is null. Id: {}", id);
              }
          } else {
              log.warn("Clients connection is null. Id: {}", id);
          }
      }
docs: Associate connection with client
  
  @param conn
  Connection object