code: public void compose(StylesheetRoot sroot) throws TransformerException
    {
      super.compose(sroot);
      StylesheetRoot.ComposeState cstate = sroot.getComposeState();
      java.util.Vector vnames = cstate.getVariableNames();
      if (null != m_avts)
      {
        int nAttrs = m_avts.size();
  
        for (int i = (nAttrs - 1); i >= 0; i--)
        {
          AVT avt = (AVT) m_avts.get(i);
          avt.fixupVariables(vnames, cstate.getGlobalsSize());
        } 
      }   
    }
docs: This function is called after everything else has been
  recomposed, and allows the template to set remaining
  values that may be based on some other property that
  depends on recomposition.