public void addLiteralResultAttribute(AVT avt){
  if (null == m_avts)   m_avts=new ArrayList();
  m_avts.add(avt);
}

public void addLiteralResultAttribute ( AVT avt ) { if ( null == m_avts ) m_avts = new ArrayList ( ) ; m_avts . add ( avt ) ; }
set a literal result attribute ( avts only ) .
