code: private static String decompress(File file) throws IOException {
          if (file == null || !file.exists()) {
              return Constants.EMPTY_STRING;
          }
  
          byte[] bytes = Base64.getDecoder().decode(IOUtils.toByteArray(new FileInputStream(file)));
          GZIPInputStream gzipInputStream = new GZIPInputStream(new ByteArrayInputStream(bytes));
          BufferedReader bf = new BufferedReader(new InputStreamReader(gzipInputStream, UTF_8));
          StringBuilder outStr = new StringBuilder(Constants.EMPTY_STRING);
          String line;
          while ((line = bf.readLine()) != null) {
              outStr.append(line);
          }
          return outStr.toString();
      }
docs: /* --- Private methods ---