code: private String getPrefetch() throws Exception {
  
          long timer = 0;
          if (CmsContentService.LOG.isDebugEnabled()) {
              timer = System.currentTimeMillis();
          }
          CmsContentDefinition definition = CmsContentService.prefetch(getRequest());
          StringBuffer sb = new StringBuffer();
          String backlink = getRequest().getParameter(CmsEditor.PARAM_BACKLINK);
          if (CmsStringUtil.isEmptyOrWhitespaceOnly(backlink)) {
              backlink = CmsVaadinUtils.getWorkplaceLink();
          } else {
              backlink = link(backlink);
          }
          sb.append(wrapScript(I_CmsContentService.PARAM_BACKLINK, "='", backlink, "';\n"));
          String prefetchedData = exportDictionary(
              I_CmsContentService.DICT_CONTENT_DEFINITION,
              I_CmsContentService.class.getMethod("prefetch"),
              definition);
          sb.append(prefetchedData);
          addExternalResourceTags(sb, definition);
          if (CmsContentService.LOG.isDebugEnabled()) {
              CmsContentService.LOG.debug(
                  Messages.get().getBundle().key(
                      Messages.LOG_TAKE_PREFETCHING_TIME_FOR_RESOURCE_2,
                      definition.getSitePath(),
                      "" + (System.currentTimeMillis() - timer)));
          }
          return sb.toString();
      }
docs: Returns the prefetch data include.<p>
  
  @return the prefetch data include
  
  @throws Exception if something goes wrong