docs: public void changeSubject(final String subject) throws NoResponseException, XMPPErrorException, NotConnectedException, InterruptedException {
          Message message = createMessage();
          message.setSubject(subject);
          // Wait for an error or confirmation message back from the server.
          StanzaFilter responseFilter = new AndFilter(fromRoomGroupchatFilter, new StanzaFilter() {
              @Override
              public boolean accept(Stanza packet) {
                  Message msg = (Message) packet;
                  return subject.equals(msg.getSubject());
              }
          });
          StanzaCollector response = connection.createStanzaCollectorAndSend(responseFilter, message);
          // Wait up to a certain number of seconds for a reply.
          response.nextResultOrThrow();
      }