code: public void outputNotify(OutputStream out, int action, Object ignoredData)
          throws IOException
      {
          if (_response==null)
              return;
  
          switch(action)
          {
            case OutputObserver.__FIRST_WRITE:
                if (!_firstWrite)
                {
                    firstWrite();
                    _firstWrite=true;
                }
                break;
                
            case OutputObserver.__RESET_BUFFER:
                resetBuffer();
                break;
                
            case OutputObserver.__COMMITING:
                commit();
                break;
                
            case OutputObserver.__CLOSING:
                
                if (_response!=null)
                {
                    completing();
                    if (!_response.isCommitted() &&
                    _request.getState()==HttpMessage.__MSG_RECEIVED)
                    commit();
                }
                break;
                
            case OutputObserver.__CLOSED:
                break;
          }
      }
docs: Output Notifications.
  Trigger header and/or filters from output stream observations.
  Also finalizes method of indicating response content length.
  Called as a result of the connection subscribing for notifications
  to the HttpOutputStream.
  @see HttpOutputStream
  @param out The output stream observed.
  @param action The action.