code: public String getAbsoluteTemplateURI(String templateName, boolean includeExtension) {
          FastStringWriter buf = new FastStringWriter();
          String tmp = templateName.substring(1,templateName.length());
          if (tmp.indexOf(SLASH) > -1) {
              buf.append(SLASH);
              int i = tmp.lastIndexOf(SLASH);
              buf.append(tmp.substring(0, i));
              buf.append(SLASH_UNDR);
              buf.append(tmp.substring(i + 1,tmp.length()));
          }
          else {
              buf.append(SLASH_UNDR);
              buf.append(templateName.substring(1,templateName.length()));
          }
          if (includeExtension) {
              buf.append(EXTENSION);
          }
          String uri = buf.toString();
          buf.close();
          return uri;
      }
docs: Used to resolve template names that are not relative to a controller.
  
  @param templateName The template name normally beginning with /
  @param includeExtension The flag to include the template extension
  @return The template URI