@Override
 public void preview() throws IOException {
   String basePath = GloabConfig.get("BASE_PATH");
   mResponse.sendRedirect(
       basePath
           + "static/preview/viewer.html?file="
           + basePath
           + "static/"
           + mPreviewFile.getName());
 }
 @Override
 public File getPreviewFile() {
   return new File(GloabConfig.get("PREVIEW_FILE_PATH") + mFile.getUniqueKey());
 }