@Override
 public void transform(SolrDocument doc, int docid) {
   if (context != null && context.query != null) {
     try {
       Explanation exp = context.searcher.explain(context.query, docid);
       if (style == Style.nl) {
         doc.setField(name, SolrPluginUtils.explanationToNamedList(exp));
       } else if (style == Style.html) {
         doc.setField(name, exp.toHtml());
       } else {
         doc.setField(name, exp.toString());
       }
     } catch (IOException e) {
       e.printStackTrace();
     }
   }
 }