@Override
 public void importTemplates(Token fileNameToken) {
   String fileName = fileNameToken.getText();
   // do nothing upon syntax error
   if (fileName == null || fileName.equals("<missing STRING>")) {
     return;
   }
   fileName = Misc.strip(fileName, 1);
   STGroup g = null;
   try {
     if (fProvider.templateExists(fileName)) {
       g = new STGroup();
       g.setListener(this.getListener());
       InputStream input = fProvider.getTemplate(fileName);
       ANTLRInputStream templateStream = new ANTLRInputStream(input);
       templateStream.name = fileName;
       CompiledST code = g.loadTemplateFile("", fileName, templateStream);
       if (code == null) {
         g = null;
       }
     }
   } catch (IOException ioe) {
     errMgr.internalError(null, "can't read from " + fileName, ioe);
     g = null;
   }
   if (g == null) {
     errMgr.compileTimeError(ErrorType.CANT_IMPORT, null, fileNameToken, fileName);
   } else {
     importTemplates(g);
   }
 }
 /** Load .st as relative file name relative to root by prefix */
 public CompiledST loadTemplateFile(String prefix, String fileName) {
   ANTLRInputStream fs;
   try {
     InputStream input = fProvider.getTemplate(fileName);
     fs = new ANTLRInputStream(input, encoding);
     fs.name = fileName;
   } catch (IOException ioe) {
     // doesn't exist
     // errMgr.IOError(null, ErrorType.NO_SUCH_TEMPLATE, ioe,
     // fileName);
     return null;
   }
   return loadTemplateFile(prefix, fileName, fs);
 }
 @Override
 public void loadGroupFile(String prefix, String fileName) {
   // System.out.println("load group file prefix="+prefix+", fileName="+fileName);
   GroupParser parser = null;
   try {
     InputStream input = fProvider.getTemplate(fileName);
     ANTLRInputStream fs = new ANTLRInputStream(input, encoding);
     GroupLexer lexer = new GroupLexer(fs);
     fs.name = fileName;
     CommonTokenStream tokens = new CommonTokenStream(lexer);
     parser = new GroupParser(tokens);
     parser.group(this, prefix);
   } catch (Exception e) {
     errMgr.IOError(null, ErrorType.CANT_LOAD_GROUP_FILE, e, fileName);
   }
 }