protected void remove(Session session,CloseReason reason){
  Collection<Session> sessions=socketSessions.get(getChannelId(session));
  if (sessions != null && sessions.remove(session)) {
    fireEvent(session,reason,SESSION_CLOSED);
  }
}

protected void remove ( Session session , CloseReason reason ) { Collection < Session > sessions = socketSessions . get ( getChannelId ( session ) ) ; if ( sessions != null && sessions . remove ( session ) ) { fireEvent ( session , reason , SESSION_CLOSED ) ; } }
on close , remove given web socket session from the mapping .
