code: public void processEvent(EventObject event) // for asynchronous
    // (nonblocking) response
    // handling
    {
      synchronized (this) {
      } // wail til message sending has finished (transaction attribute set)
  
      if (event instanceof ResponseEvent) {
        processResponse((ResponseEvent) event);
      } else if (event instanceof TimeoutEvent) {
        processTimeout((TimeoutEvent) event);
      }
  
      // note, requests don't come through here, they are handled via the
      // listen/waitFor methods.
    }
docs: /*
  @see org.cafesip.sipunit.MessageListener#processEvent(java.util.EventObject)