code: private void handleInCompletedState(final SipPacket msg) throws SipPacketParseException {
          if (msg.isRequest()) {
              // TODO:
          } else {
              if (msg.isBye()) {
                  transition(CallState.COMPLETED, msg);
              }
          }
      }
docs: Handle state transitions for when we are already in the completed state.
  
  @param msg
  @throws SipPacketParseException