code: private boolean isSessionNameUnique(final String name) {
  		synchronized (this.sessions) {
  			for (HttpSession session : sessions) {
  				if (name.equals(session.getName())) {
  					return false;
  				}
  			}
  		}
  		return true;
  	}
docs: Tells whether the given session {@code name} is unique or not, compared to existing session
  names.
  
  @param name the session name that will be checked
  @return {@code true} if the session name is unique, {@code false} otherwise
  @see #sessions